The complete FUN TO IMAGINE with Richard Feynman

It's interesting that some people find science simple, while others find it tedious and difficult. Children, in particular, some children just accept things as they are. I don't know why, perhaps it's the same with all subjects. For example, many people love music, but I can never keep up with the tune. I've also missed out on a lot of enjoyment because of that. Similarly, I think those who find science boring miss out on a lot of enjoyment.

As far as science is concerned, I think one of the reasons it's made difficult is that science requires a lot of imagination. It's hard to imagine what all these strange objects were originally like. Nothing is as simple as it appears. Take, for example, the familiar concepts of hot and cold. Hot and cold depend on the speed of atomic vibration. The faster the atoms vibrate, the hotter it is, and the slower they vibrate, the colder it is.

If you have a lot of atoms, say a cup of coffee, on a table. The atoms in the cup are vibrating vigorously, constantly hitting the inside of the cup. The cup is vibrated, and so the atoms in the cup itself also vibrate more intensely. They hit each other, the cup is heated, and everything around it is heated. Then, hot things transfer heat to other things simply by contact. This is because the atoms in hot objects vibrate more vigorously. This causes the inactive atoms in cold objects to start vibrating. Thus, heat enters the cold object, and heat is transferred. But it's only the vibration that's transferred, a random motion, which is easy to understand.

This leads to another interesting point: when I say objects vibrate, you imagine little balls bouncing. You know that this bouncing gradually slows down and stops after a while. But we have to imagine that atoms are perfectly elastic; they don't lose any energy. They keep hitting, always hitting, but without losing any energy. They are in perpetual motion. Whereas the motion of objects that lose energy, like a ball bouncing on the floor. It randomly transmits vibrations to some atoms in the floor. When the ball bounces up, it leaves behind a bunch of atoms vibrating more vigorously. So, as the ball bounces, it transfers its excess energy, its excess motion, to the atoms in the floor. Each time it bounces, it loses a little bit of heat. Until it stops, at which point we say its falling motion has ended. But what's left behind is that the atoms in the floor are vibrating more vigorously than before, and the atoms in the ball are also vibrating more vigorously. Originally, all the atoms in the ball were moving in an orderly fashion, falling. And the floor was calm. Now it's a ball resting on the floor. But all the motion still exists in the form of kinetic energy. The vibration of the atoms in the floor makes the floor a little warmer, incredibly!

But those who hammer things often know this is true. If you hit something, hit it many times, you can feel the temperature rise, it gets a little hot. The object being hit gets hot simply because you are making it vibrate. This picture of atoms is extremely beautiful. You can observe all sorts of things in this way. You observe a small drop of water, a very small drop. The atoms attract each other; they like to be together. They want to have as many companions as possible. And the atoms on the surface of the water drop now have companions on only one side. The other side is air, so they want to get in. You can imagine a crowd of people, all moving rapidly, all wanting as many companions as possible. Those at the edge are unhappy, very tense, they keep bumping, trying to get in. This forms a tight ball, rather than spreading out into a sheet. This is surface tension. Sometimes when you see a drop of water standing on a table like a ball, you start to wonder why it's like that. Because every atom wants to get into the water. As they try to get in, atoms are also leaving the surface. So the drop of water slowly disappears.

I find myself constantly trying to imagine all these phenomena. I get pleasure from imagining, just as a runner gets pleasure from sweating. I get joy from thinking about these phenomena. I can't stop; I could go on and on. If you can cool water, then the atoms vibrate less and less, vibrating more and more slowly. Then the atoms will be confined to a region. They like to be with their companions. There is attraction, so they will crowd together. They won't push each other, and they will form beautiful patterns. Like oranges neatly arranged in a fruit crate, each can only wiggle in its fixed position. But they don't have enough kinetic energy to break free from their confined positions and disrupt the structure. What I'm describing is a solid state, i.e., ice, which has a structure. If you place atoms in a specific position, then the rest of the atoms line up, eventually forming a solid.

And if you keep heating them, then they start to lose their bonds and roll over each other. This is the liquid state. And if you heat them even more vigorously, then they will bounce more intensely. They will hit each other and bounce apart. So they become individual. Although what I call atoms are actually combinations of atoms, molecules. Molecules fly around and collide. Although they tend to stay together, they move too fast. In common terms, when they meet head-on, their "hands" can't hold on, so they fly apart again. This gaseous state is what we call "steam." You will gain an understanding of various phenomena.

When I was a child, I was always interested in "air." I noticed that when I pumped up my bicycle tire (there's a lot you can learn from a bicycle). I pumped up the tire, and the pump got hot. This is actually easy to understand. As the pump's piston pushes down, the atoms hit it and bounce back, but the piston is moving downwards. The speed of the atoms after bouncing off the piston is greater than before they hit it. So, as the piston continues to move down, the atoms' speed increases with each collision. So when you compress a gas, it heats up. And when you pull the piston out, fast-moving atoms hit the piston and lose some kinetic energy, so the atoms' energy decreases. It's like punching cotton; it sinks in, "bang bang." Energy is lost. When you pull the piston out, the atoms hit it and their speed decreases, so the temperature drops. So when a gas expands, its temperature decreases.

The interesting thing is that all the phenomena you observe in this world, such as your gas compressing and heating up, expanding and cooling down, or water evaporating from a cup if it's not covered. All these phenomena can be understood using a simple atomic picture. Thinking this way is very interesting. I don't want to take this kind of thinking too seriously. I think we should imagine happily, without any worries. There won't be a teacher asking questions at the end, otherwise it's an annoying subject.

Different atoms want to be close to each other to varying degrees. For example, oxygen atoms in the air want to be close to carbon atoms. If they get too close, they combine vigorously. If they are not very close, they repel each other and separate. So they don't know they can combine. It's like a ball trying to climb a hill. There's a hole in front of it, into which it can fall, like a crater. A deep opening. The ball just circles around it and doesn't fall in. Because when the ball starts to climb the slope, it rolls back. But if you make it go fast enough to pass the critical point, it will fall into the hole. So if something like wood comes into contact with oxygen, and there are carbon atoms in the wood. The oxygen atoms come and hit the carbon atoms, but the temperature isn't high enough. The oxygen atoms run away again. Air always comes and goes, and nothing happens.

If you heat the oxygen atoms in some way to make them faster, to accelerate a few atoms at first, meaning to get them past the critical point. They get close enough to the carbon atoms, and then they combine vigorously. This will produce more vigorous vibrations, possibly hitting other atoms and making them move faster, so they can pass the critical point and hit other carbon atoms. Their continuous vibration causes other atoms to vibrate together, and a terrible disaster occurs. One atom after another vibrates faster and faster, combining vigorously, and everything changes. This "disaster" is fire. This is one way to describe "fire." This collision is constantly happening, never stopping. Once it starts, it continues to do so. The heat produced gives other atoms the ability to collide and produce more heat, causing more atoms to behave the same way. So this vigorous combination triggers a lot of vibration.

If I place those less energetic atoms over there, for example, if I place a cup of cold coffee next to a pile of burning wood. The atoms in the coffee will vibrate vigorously, that's the heat of the fire. Of course, there will be... See, this is what happens when you start thinking, you can't stop at all. You just want to know how it started. Why did the wood stay with the oxygen for so long without fire appearing before? Where did this heat come from? Actually, it comes from the tree. The substance of the tree is carbon. Where did that carbon come from? It comes from carbon dioxide in the air. People look at trees and think trees grow from the ground. Plants grow from the ground. But if you ask where the substance of the tree comes from, think carefully about where it comes from. Does the tree come from the air? Of course, trees do come from the air. Carbon dioxide in the air enters the tree, changes, kicks out oxygen atoms, forming oxygen and releasing it, leaving carbon atoms. Carbon and water form the substance of the tree. Water comes from the ground, and carbon atoms enter the tree from the air, right? It comes from the sky. Therefore, almost all trees come from the ground. Sorry, I misspoke, they all come from the air. Of course, a small amount comes from underground minerals, etc.

Of course, I told you oxygen atoms... Oxygen atoms and carbon atoms combine very tightly. So how does the tree cleverly absorb carbon dioxide? At this point, the carbon atoms and oxygen atoms are tightly bound, yet the tree can easily break them down? Ah! Life, is it some mysterious power of life? Wrong, it's the sun's rays. Sunlight shines in and separates the oxygen atoms and carbon atoms. Therefore, sunlight is needed for plants to grow. So the role of the sun is to continuously separate oxygen atoms and carbon atoms. Oxygen, as a kind of bad byproduct, is released into the air, leaving behind carbon atoms and water, which form the substance of the tree. Then we put the substance of the tree in the fireplace. The oxygen produced by the tree wants to combine with the carbon in the tree again. Once you heat it to trigger their combination, the whole process will continue. During their vigorous combination, intense thermal motion will occur. Thus, beautiful light and other things appear. It's as if nothing happened; you've turned oxygen and carbon back into carbon dioxide. But light and heat are produced, which are actually the light and heat of the sun radiating in. So when you light a piece of wood, it's like releasing the sun stored in the wood.

The next question is, why is the sun so active and so hot? I'll stop here and leave you with a question to imagine. Most elastic things, like steel bars or springs, are due to forces related to electricity pulling them back. When you bend something, you're pulling the atoms a little farther apart, so these atoms try to come back together. But a rubber band works differently. There are some long chain-like molecules, and some small molecules that are constantly vibrating and hitting these chain molecules. And the chain molecules are all twisted and funny shapes. When you straighten the rubber band, the chain molecules straighten out. But these chain molecules are constantly being hit from the sides. Other atoms try to twist them, making them contract. Therefore, the rubber band tries to contract. It contracts simply due to heat. So if you heat a rubber band, it will contract more. For example, if you hang a heavy object with a rubber band and then bring a lit match close to the rubber band, it's quite interesting to watch the heavy object rise as the rubber band is heated.

You can also prove this point in another way. To prove that it is indeed heat that drives the contraction of a rubber band. When you stretch a rubber band, it's like compressing the piston and internal gas downwards. If you stretch a rubber band, the stretched chain molecules hit other molecules, making them move faster, so the temperature rises. And when you contract the rubber band, the molecules lose some energy when they hit the chain molecules. It's like hitting something soft; it sinks in and "bang bang." Energy is lost. When you pull the piston out, the atoms hit it and their speed decreases, so the temperature drops. So when a gas expands, its temperature decreases.

The interesting thing is that all the phenomena you observe in this world, such as your gas compressing and heating up, expanding and cooling down, or water evaporating from a cup if it's not covered. All these phenomena can be understood using a simple atomic picture. Thinking this way is very interesting. I don't want to take this kind of thinking too seriously. I think we should imagine happily, without any worries. There won't be a teacher asking questions at the end, otherwise it's an annoying subject.

Different atoms want to be close to each other to varying degrees. For example, oxygen atoms in the air want to be close to carbon atoms. If they get too close, they combine vigorously. If they are not very close, they repel each other and separate. So they don't know they can combine. It's like a ball trying to climb a hill. There's a hole in front of it, into which it can fall, like a crater. A deep opening. The ball just circles around it and doesn't fall in. Because when the ball starts to climb the slope, it rolls back. But if you make it go fast enough to pass the critical point, it will fall into the hole. So if something like wood comes into contact with oxygen, and there are carbon atoms in the wood. The oxygen atoms come and hit the carbon atoms, but the temperature isn't high enough. The oxygen atoms run away again. Air always comes and goes, and nothing happens.

If you heat the oxygen atoms in some way to make them faster, to accelerate a few atoms at first, meaning to get them past the critical point. They get close enough to the carbon atoms, and then they combine vigorously. This will produce more vigorous vibrations, possibly hitting other atoms and making them move faster, so they can pass the critical point and hit other carbon atoms. Their continuous vibration causes other atoms to vibrate together, and a terrible disaster occurs. One atom after another vibrates faster and faster, combining vigorously, and everything changes. This "disaster" is fire. This is one way to describe "fire." This collision is constantly happening, never stopping. Once it starts, it continues to do so. The heat produced gives other atoms the ability to collide and produce more heat, causing more atoms to behave the same way. So this vigorous combination triggers a lot of vibration.

If I place those less energetic atoms over there, for example, if I place a cup of cold coffee next to a pile of burning wood. The atoms in the coffee will vibrate vigorously, that's the heat of the fire. Of course, there will be... See, this is what happens when you start thinking, you can't stop at all. You just want to know how it started. Why did the wood stay with the oxygen for so long without fire appearing before? Where did this heat come from? Actually, it comes from the tree. The substance of the tree is carbon. Where did that carbon come from? It comes from carbon dioxide in the air. People look at trees and think trees grow from the ground. Plants grow from the ground. But if you ask where the substance of the tree comes from, think carefully about where it comes from. Does the tree come from the air? Of course, trees do come from the air. Carbon dioxide in the air enters the tree, changes, kicks out oxygen atoms, forming oxygen and releasing it, leaving carbon atoms. Carbon and water form the substance of the tree. Water comes from the ground, and carbon atoms enter the tree from the air, right? It comes from the sky. Therefore, almost all trees come from the ground. Sorry, I misspoke, they all come from the air. Of course, a small amount comes from underground minerals, etc.

Of course, I told you oxygen atoms... Oxygen atoms and carbon atoms combine very tightly. So how does the tree cleverly absorb carbon dioxide? At this point, the carbon atoms and oxygen atoms are tightly bound, yet the tree can easily break them down? Ah! Life, is it some mysterious power of life? Wrong, it's the sun's rays. Sunlight shines in and separates the oxygen atoms and carbon atoms. Therefore, sunlight is needed for plants to grow. So the role of the sun is to continuously separate oxygen atoms and carbon atoms. Oxygen, as a kind of bad byproduct, is released into the air, leaving behind carbon atoms and water, which form the substance of the tree. Then we put the substance of the tree in the fireplace. The oxygen produced by the tree wants to combine with the carbon in the tree again. Once you heat it to trigger their combination, the whole process will continue. During their vigorous combination, intense thermal motion will occur. Thus, beautiful light and other things appear. It's as if nothing happened; you've turned oxygen and carbon back into carbon dioxide. But light and heat are produced, which are actually the light and heat of the sun radiating in. So when you light a piece of wood, it's like releasing the sun stored in the wood.

The next question is, why is the sun so active and so hot? I'll stop here and leave you with a question to imagine. Most elastic things, like steel bars or springs, are due to forces related to electricity pulling them back. When you bend something, you're pulling the atoms a little farther apart, so these atoms try to come back together. But a rubber band works differently. There are some long chain-like molecules, and some small molecules that are constantly vibrating and hitting these chain molecules. And the chain molecules are all twisted and funny shapes. When you straighten the rubber band, the chain molecules straighten out. But these chain molecules are constantly being hit from the sides. Other atoms try to twist them, making them contract. Therefore, the rubber band tries to contract. It contracts simply due to heat. So if you heat a rubber band, it will contract more. For example, if you hang a heavy object with a rubber band and then bring a lit match close to the rubber band, it's quite interesting to watch the heavy object rise as the rubber band is heated.

You can also prove this point in another way. To prove that it is indeed heat that drives the contraction of a rubber band. When you stretch a rubber band, it's like compressing the piston and internal gas downwards. If you stretch a rubber band, the stretched chain molecules hit other molecules, making them move faster, so the temperature rises. And when you contract the rubber band, the molecules lose some energy when they hit the chain molecules. It's like hitting something soft; it sinks in and "bang bang." Energy is lost. When you pull the piston out, the atoms hit it and their speed decreases, so the temperature drops. So when a gas expands, its temperature decreases.

The interesting thing is that all the phenomena you observe in this world, such as your gas compressing and heating up, expanding and cooling down, or water evaporating from a cup if it's not covered. All these phenomena can be understood using a simple atomic picture. Thinking this way is very interesting. I don't want to take this kind of thinking too seriously. I think we should imagine happily, without any worries. There won't be a teacher asking questions at the end, otherwise it's an annoying subject.

Different atoms want to be close to each other to varying degrees. For example, oxygen atoms in the air want to be close to carbon atoms. If they get too close, they combine vigorously. If they are not very close, they repel each other and separate. So they don't know they can combine. It's like a ball trying to climb a hill. There's a hole in front of it, into which it can fall, like a crater. A deep opening. The ball just circles around it and doesn't fall in. Because when the ball starts to climb the slope, it rolls back. But if you make it go fast enough to pass the critical point, it will fall into the hole. So if something like wood comes into contact with oxygen, and there are carbon atoms in the wood. The oxygen atoms come and hit the carbon atoms, but the temperature isn't high enough. The oxygen atoms run away again. Air always comes and goes, and nothing happens.

If you heat the oxygen atoms in some way to make them faster, to accelerate a few atoms at first, meaning to get them past the critical point. They get close enough to the carbon atoms, and then they combine vigorously. This will produce more vigorous vibrations, possibly hitting other atoms and making them move faster, so they can pass the critical point and hit other carbon atoms. Their continuous vibration causes other atoms to vibrate together, and a terrible disaster occurs. One atom after another vibrates faster and faster, combining vigorously, and everything changes. This "disaster" is fire. This is one way to describe "fire." This collision is constantly happening, never stopping. Once it starts, it continues to do so. The heat produced gives other atoms the ability to collide and produce more heat, causing more atoms to behave the same way. So this vigorous combination triggers a lot of vibration.

If I place those less energetic atoms over there, for example, if I place a cup of cold coffee next to a pile of burning wood. The atoms in the coffee will vibrate vigorously, that's the heat of the fire. Of course, there will be... See, this is what happens when you start thinking, you can't stop at all. You just want to know how it started. Why did the wood stay with the oxygen for so long without fire appearing before? Where did this heat come from? Actually, it comes from the tree. The substance of the tree is carbon. Where did that carbon come from? It comes from carbon dioxide in the air. People look at trees and think trees grow from the ground. Plants grow from the ground. But if you ask where the substance of the tree comes from, think carefully about where it comes from. Does the tree come from the air? Of course, trees do come from the air. Carbon dioxide in the air enters the tree, changes, kicks out oxygen atoms, forming oxygen and releasing it, leaving carbon atoms. Carbon and water form the substance of the tree. Water comes from the ground, and carbon atoms enter the tree from the air, right? It comes from the sky. Therefore, almost all trees come from the ground. Sorry, I misspoke, they all come from the air. Of course, a small amount comes from underground minerals, etc.

Of course, I told you oxygen atoms... Oxygen atoms and carbon atoms combine very tightly. So how does the tree cleverly absorb carbon dioxide? At this point, the carbon atoms and oxygen atoms are tightly bound, yet the tree can easily break them down? Ah! Life, is it some mysterious power of life? Wrong, it's the sun's rays. Sunlight shines in and separates the oxygen atoms and carbon atoms. Therefore, sunlight is needed for plants to grow. So the role of the sun is to continuously separate oxygen atoms and carbon atoms. Oxygen, as a kind of bad byproduct, is released into the air, leaving behind carbon atoms and water, which form the substance of the tree. Then we put the substance of the tree in the fireplace. The oxygen produced by the tree wants to combine with the carbon in the tree again. Once you heat it to trigger their combination, the whole process will continue. During their vigorous combination, intense thermal motion will occur. Thus, beautiful light and other things appear. It's as if nothing happened; you've turned oxygen and carbon back into carbon dioxide. But light and heat are produced, which are actually the light and heat of the sun radiating in. So when you light a piece of wood, it's like releasing the sun stored in the wood.

The next question is, why is the sun so active and so hot? I'll stop here and leave you with a question to imagine. Most elastic things, like steel bars or springs, are due to forces related to electricity pulling them back. When you bend something, you're pulling the atoms a little farther apart, so these atoms try to come back together. But a rubber band works differently. There are some long chain-like molecules, and some small molecules that are constantly vibrating and hitting these chain molecules. And the chain molecules are all twisted and funny shapes. When you straighten the rubber band, the chain molecules straighten out. But these chain molecules are constantly being hit from the sides. Other atoms try to twist them, making them contract. Therefore, the rubber band tries to contract. It contracts simply due to heat. So if you heat a rubber band, it will contract more. For example, if you hang a heavy object with a rubber band and then bring a lit match close to the rubber band, it's quite interesting to watch the heavy object rise as the rubber band is heated.

You can also prove this point in another way. To prove that it is indeed heat that drives the contraction of a rubber band. When you stretch a rubber band, it's like compressing the piston and internal gas downwards. If you stretch a rubber band, the stretched chain molecules hit other molecules, making them move faster, so the temperature rises. And when you contract the rubber band, the molecules lose some energy when they hit the chain molecules. It's like hitting something soft; it sinks in and "bang bang." Energy is lost. When you pull the piston out, the atoms hit it and their speed decreases, so the temperature drops. So when a gas expands, its temperature decreases.

The interesting thing is that all the phenomena you observe in this world, such as your gas compressing and heating up, expanding and cooling down, or water evaporating from a cup if it's not covered. All these phenomena can be understood using a simple atomic picture. Thinking this way is very interesting. I don't want to take this kind of thinking too seriously. I think we should imagine happily, without any worries. There won't be a teacher asking questions at the end, otherwise it's an annoying subject.

Different atoms want to be close to each other to varying degrees. For example, oxygen atoms in the air want to be close to carbon atoms. If they get too close, they combine vigorously. If they are not very close, they repel each other and separate. So they don't know they can combine. It's like a ball trying to climb a hill. There's a hole in front of it, into which it can fall, like a crater. A deep opening. The ball just circles around it and doesn't fall in. Because when the ball starts to climb the slope, it rolls back. But if you make it go fast enough to pass the critical point, it will fall into the hole. So if something like wood comes into contact with oxygen, and there are carbon atoms in the wood. The oxygen atoms come and hit the carbon atoms, but the temperature isn't high enough. The oxygen atoms run away again. Air always comes and goes, and nothing happens.

If you heat the oxygen atoms in some way to make them faster, to accelerate a few atoms at first, meaning to get them past the critical point. They get close enough to the carbon atoms, and then they combine vigorously. This will produce more vigorous vibrations, possibly hitting other atoms and making them move faster, so they can pass the critical point and hit other carbon atoms. Their continuous vibration causes other atoms to vibrate together, and a terrible disaster occurs. One atom after another vibrates faster and faster, combining vigorously, and everything changes. This "disaster" is fire. This is one way to describe "fire." This collision is constantly happening, never stopping. Once it starts, it continues to do so. The heat produced gives other atoms the ability to collide and produce more heat, causing more atoms to behave the same way. So this vigorous combination triggers a lot of vibration.

If I place those less energetic atoms over there, for example, if I place a cup of cold coffee next to a pile of burning wood. The atoms in the coffee will vibrate vigorously, that's the heat of the fire. Of course, there will be... See, this is what happens when you start thinking, you can't stop at all. You just want to know how it started. Why did the wood stay with the oxygen for so long without fire appearing before? Where did this heat come from? Actually, it comes from the tree. The substance of the tree is carbon. Where did that carbon come from? It comes from carbon dioxide in the air. People look at trees and think trees grow from the ground. Plants grow from the ground. But if you ask where the substance of the tree comes from, think carefully about where it comes from. Does the tree come from the air? Of course, trees do come from the air. Carbon dioxide in the air enters the tree, changes, kicks out oxygen atoms, forming oxygen and releasing it, leaving carbon atoms. Carbon and water form the substance of the tree. Water comes from the ground, and carbon atoms enter the tree from the air, right? It comes from the sky. Therefore, almost all trees come from the ground. Sorry, I misspoke, they all come from the air. Of course, a small amount comes from underground minerals, etc.

Of course, I told you oxygen atoms... Oxygen atoms and carbon atoms combine very tightly. So how does the tree cleverly absorb carbon dioxide? At this point, the carbon atoms and oxygen atoms are tightly bound, yet the tree can easily break them down? Ah! Life, is it some mysterious power of life? Wrong, it's the sun's rays. Sunlight shines in and separates the oxygen atoms and carbon atoms. Therefore, sunlight is needed for plants to grow. So the role of the sun is to continuously separate oxygen atoms and carbon atoms. Oxygen, as a kind of bad byproduct, is released into the air, leaving behind carbon atoms and water, which form the substance of the tree. Then we put the substance of the tree in the fireplace. The oxygen produced by the tree wants to combine with the carbon in the tree again. Once you heat it to trigger their combination, the whole process will continue. During their vigorous combination, intense thermal motion will occur. Thus, beautiful light and other things appear. It's as if nothing happened; you've turned oxygen and carbon back into carbon dioxide. But light and heat are produced, which are actually the light and heat of the sun radiating in. So when you light a piece of wood, it's like releasing the sun stored in the wood.

The next question is, why is the sun so active and so hot? I'll stop here and leave you with a question to imagine. Most elastic things, like steel bars or springs, are due to forces related to electricity pulling them back. When you bend something, you're pulling the atoms a little farther apart, so these atoms try to come back together. But a rubber band works differently. There are some long chain-like molecules, and some small molecules that are constantly vibrating and hitting these chain molecules. And the chain molecules are all twisted and funny shapes. When you straighten the rubber band, the chain molecules straighten out. But these chain molecules are constantly being hit from the sides. Other atoms try to twist them, making them contract. Therefore, the rubber band tries to contract. It contracts simply due to heat. So if you heat a rubber band, it will contract more. For example, if you hang a heavy object with a rubber band and then bring a lit match close to the rubber band, it's quite interesting to watch the heavy object rise as the rubber band is heated.

You can also prove this point in another way. To prove that it is indeed heat that drives the contraction of a rubber band. When you stretch a rubber band, it's like compressing the piston and internal gas downwards. If you stretch a rubber band, the stretched chain molecules hit other molecules, making them move faster, so the temperature rises. And when you contract the rubber band, the molecules lose some energy when they hit the chain molecules. It's like hitting something soft; it sinks in and "bang bang." Energy is lost. When you pull the piston out, the atoms hit it and their speed decreases, so the temperature drops. So when a gas expands, its temperature decreases.

The interesting thing is that all the phenomena you observe in this world, such as your gas compressing and heating up, expanding and cooling down, or water evaporating from a cup if it's not covered. All these phenomena can be understood using a simple atomic picture. Thinking this way is very interesting. I don't want to take this kind of thinking too seriously. I think we should imagine happily, without any worries. There won't be a teacher asking questions at the end, otherwise it's an annoying subject.

Different atoms want to be close to each other to varying degrees. For example, oxygen atoms in the air want to be close to carbon atoms. If they get too close, they combine vigorously. If they are not very close, they repel each other and separate. So they don't know they can combine. It's like a ball trying to climb a hill. There's a hole in front of it, into which it can fall, like a crater. A deep opening. The ball just circles around it and doesn't fall in. Because when the ball starts to climb the slope, it rolls back. But if you make it go fast enough to pass the critical point, it will fall into the hole. So if something like wood comes into contact with oxygen, and there are carbon atoms in the wood. The oxygen atoms come and hit the carbon atoms, but the temperature isn't high enough. The oxygen atoms run away again. Air always comes and goes, and nothing happens.

If you heat the oxygen atoms in some way to make them faster, to accelerate a few atoms at first, meaning to get them past the critical point. They get close enough to the carbon atoms, and then they combine vigorously. This will produce more vigorous vibrations, possibly hitting other atoms and making them move faster, so they can pass the critical point and hit other carbon atoms. Their continuous vibration causes other atoms to vibrate together, and a terrible disaster occurs. One atom after another vibrates faster and faster, combining vigorously, and everything changes. This "disaster" is fire. This is one way to describe "fire." This collision is constantly happening, never stopping. Once it starts, it continues to do so. The heat produced gives other atoms the ability to collide and produce more heat, causing more atoms to behave the same way. So this vigorous combination triggers a lot of vibration.

If I place those less energetic atoms over there, for example, if I place a cup of cold coffee next to a pile of burning wood. The atoms in the coffee will vibrate vigorously, that's the heat of the fire. Of course, there will be... See, this is what happens when you start thinking, you can't stop at all. You just want to know how it started. Why did the wood stay with the oxygen for so long without fire appearing before? Where did this heat come from? Actually, it comes from the tree. The substance of the tree is carbon. Where did that carbon come from? It comes from carbon dioxide in the air. People look at trees and think trees grow from the ground. Plants grow from the ground. But if you ask where the substance of the tree comes from, think carefully about where it comes from. Does the tree come from the air? Of course, trees do come from the air. Carbon dioxide in the air enters the tree, changes, kicks out oxygen atoms, forming oxygen and releasing it, leaving carbon atoms. Carbon and water form the substance of the tree. Water comes from the ground, and carbon atoms enter the tree from the air, right? It comes from the sky. Therefore, almost all trees come from the ground. Sorry, I misspoke, they all come from the air. Of course, a small amount comes from underground minerals, etc.

Of course, I told you oxygen atoms... Oxygen atoms and carbon atoms combine very tightly. So how does the tree cleverly absorb carbon dioxide? At this point, the carbon atoms and oxygen atoms are tightly bound, yet the tree can easily break them down? Ah! Life, is it some mysterious power of life? Wrong, it's the sun's rays. Sunlight shines in and separates the oxygen atoms and carbon atoms. Therefore, sunlight is needed for plants to grow. So the role of the sun is to continuously separate oxygen atoms and carbon atoms. Oxygen, as a kind of bad byproduct, is released into the air, leaving behind carbon atoms and water, which form the substance of the tree. Then we put the substance of the tree in the fireplace. The oxygen produced by the tree wants to combine with the carbon in the tree again. Once you heat it to trigger their combination, the whole process will continue. During their vigorous combination, intense thermal motion will occur. Thus, beautiful light and other things appear. It's as if nothing happened; you've turned oxygen and carbon back into carbon dioxide. But light and heat are produced, which are actually the light and heat of the sun radiating in. So when you light a piece of wood, it's like releasing the sun stored in the wood.

The next question is, why is the sun so active and so hot? I'll stop here and leave you with a question to imagine. Most elastic things, like steel bars or springs, are due to forces related to electricity pulling them back. When you bend something, you're pulling the atoms a little farther apart, so these atoms try to come back together. But a rubber band works differently. There are some long chain-like molecules, and some small molecules that are constantly vibrating and hitting these chain molecules. And the chain molecules are all twisted and funny shapes. When you straighten the rubber band, the chain molecules straighten out. But these chain molecules are constantly being hit from the sides. Other atoms try to twist them, making them contract. Therefore, the rubber band tries to contract. It contracts simply due to heat. So if you heat a rubber band, it will contract more. For example, if you hang a heavy object with a rubber band and then bring a lit match close to the rubber band, it's quite interesting to watch the heavy object rise as the rubber band is heated.

You can also prove this point in another way. To prove that it is indeed heat that drives the contraction of a rubber band. When you stretch a rubber band, it's like compressing the piston and internal gas downwards. If you stretch a rubber band, the stretched chain molecules hit other molecules, making them move faster, so the temperature rises. And when you contract the rubber band, the molecules lose some energy when they hit the chain molecules. It's like hitting something soft; it sinks in and "bang bang." Energy is lost. When you pull the piston out, the atoms hit it and their speed decreases, so the temperature drops. So when a gas expands, its temperature decreases.

The interesting thing is that all the phenomena you observe in this world, such as your gas compressing and heating up, expanding and cooling down, or water evaporating from a cup if it's not covered. All these phenomena can be understood using a simple atomic picture. Thinking this way is very interesting. I don't want to take this kind of thinking too seriously. I think we should imagine happily, without any worries. There won't be a teacher asking questions at the end, otherwise it's an annoying subject.

Different atoms want to be close to each other to varying degrees. For example, oxygen atoms in the air want to be close to carbon atoms. If they get too close, they combine vigorously. If they are not very close, they repel each other and separate. So they don't know they can combine. It's like a ball trying to climb a hill. There's a hole in front of it, into which it can fall, like a crater. A deep opening. The ball just circles around it and doesn't fall in. Because when the ball starts to climb the slope, it rolls back. But if you make it go fast enough to pass the critical point, it will fall into the hole. So if something like wood comes into contact with oxygen, and there are carbon atoms in the wood. The oxygen atoms come and hit the carbon atoms, but the temperature isn't high enough. The oxygen atoms run away again. Air always comes and goes, and nothing happens.

If you heat the oxygen atoms in some way to make them faster, to accelerate a few atoms at first, meaning to get them past the critical point. They get close enough to the carbon atoms, and then they combine vigorously. This will produce more vigorous vibrations, possibly hitting other atoms and making them move faster, so they can pass the critical point and hit other carbon atoms. Their continuous vibration causes other atoms to vibrate together, and a terrible disaster occurs. One atom after another vibrates faster and faster, combining vigorously, and everything changes. This "disaster" is fire. This is one way to describe "fire." This collision is constantly happening, never stopping. Once it starts, it continues to do so. The heat produced gives other atoms the ability to collide and produce more heat, causing more atoms to behave the same way. So this vigorous combination triggers a lot of vibration.

If I place those less energetic atoms over there, for example, if I place a cup of cold coffee next to a pile of burning wood. The atoms in the coffee will vibrate vigorously, that's the heat of the fire. Of course, there will be... See, this is what happens when you start thinking, you can't stop at all. You just want to know how it started. Why did the wood stay with the oxygen for so long without fire appearing before? Where did this heat come from? Actually, it comes from the tree. The substance of the tree is carbon. Where did that carbon come from? It comes from carbon dioxide in the air. People look at trees and think trees grow from the ground. Plants grow from the ground. But if you ask where the substance of the tree comes from, think carefully about where it comes from. Does the tree come from the air? Of course, trees do come from the air. Carbon dioxide in the air enters the tree, changes, kicks out oxygen atoms, forming oxygen and releasing it, leaving carbon atoms. Carbon and water form the substance of the tree. Water comes from the ground, and carbon atoms enter the tree from the air, right? It comes from the sky. Therefore, almost all trees come from the ground. Sorry, I misspoke, they all come from the air. Of course, a small amount comes from underground minerals, etc.

Of course, I told you oxygen atoms... Oxygen atoms and carbon atoms combine very tightly. So how does the tree cleverly absorb carbon dioxide? At this point, the carbon atoms and oxygen atoms are tightly bound, yet the tree can easily break them down? Ah! Life, is it some mysterious power of life? Wrong, it's the sun's rays. Sunlight shines in and separates the oxygen atoms and carbon atoms. Therefore, sunlight is needed for plants to grow. So the role of the sun is to continuously separate oxygen atoms and carbon atoms. Oxygen, as a kind of bad byproduct, is released into the air, leaving behind carbon atoms and water, which form the substance of the tree. Then we put the substance of the tree in the fireplace. The oxygen produced by the tree wants to combine with the carbon in the tree again. Once you heat it to trigger their combination, the whole process will continue. During their vigorous combination, intense thermal motion will occur. Thus, beautiful light and other things appear. It's as if nothing happened; you've turned oxygen and carbon back into carbon dioxide. But light and heat are produced, which are actually the light and heat of the sun radiating in. So when you light a piece of wood, it's like releasing the sun stored in the wood.

The next question is, why is the sun so active and so hot? I'll stop here and leave you with a question to imagine. Most elastic things, like steel bars or springs, are due to forces related to electricity pulling them back. When you bend something, you're pulling the atoms a little farther apart, so these atoms try to come back together. But a rubber band works differently. There are some long chain-like molecules, and some small molecules that are constantly vibrating and hitting these chain molecules. And the chain molecules are all twisted and funny shapes. When you straighten the rubber band, the chain molecules straighten out. But these chain molecules are constantly being hit from the sides. Other atoms try to twist them, making them contract. Therefore, the rubber band tries to contract. It contracts simply due to heat. So if you heat a rubber band, it will contract more. For example, if you hang a heavy object with a rubber band and then bring a lit match close to the rubber band, it's quite interesting to watch the heavy object rise as the rubber band is heated.

You can also prove this point in another way. To prove that it is indeed heat that drives the contraction of a rubber band. When you stretch a rubber band, it's like compressing the piston and internal gas downwards. If you stretch a rubber band, the stretched chain molecules hit other molecules, making them move faster, so the temperature rises. And when you contract the rubber band, the molecules lose some energy when they hit the chain molecules. It's like hitting something soft; it sinks in and "bang bang." Energy is lost. When you pull the piston out, the atoms hit it and their speed decreases, so the temperature drops. So when a gas expands, its temperature decreases.

The interesting thing is that all the phenomena you observe in this world, such as your gas compressing and heating up, expanding and cooling down, or water evaporating from a cup if it's not covered. All these phenomena can be understood using a simple atomic picture. Thinking this way is very interesting. I don't want to take this kind of thinking too seriously. I think we should imagine happily, without any worries. There won't be a teacher asking questions at the end, otherwise it's an annoying subject.

Different atoms want to be close to each other to varying degrees. For example, oxygen atoms in the air want to be close to carbon atoms. If they get too close, they combine vigorously. If they are not very close, they repel each other and separate. So they don't know they can combine. It's like a ball trying to climb a hill. There's a hole in front of it, into which it can fall, like a crater. A deep opening. The ball just circles around it and doesn't fall in. Because when the ball starts to climb the slope, it rolls back. But if you make it go fast enough to pass the critical point, it will fall into the hole. So if something like wood comes into contact with oxygen, and there are carbon atoms in the wood. The oxygen atoms come and hit the carbon atoms, but the temperature isn't high enough. The oxygen atoms run away again. Air always comes and goes, and nothing happens.

If you heat the oxygen atoms in some way to make them faster, to accelerate a few atoms at first, meaning to get them past the critical point. They get close enough to the carbon atoms, and then they combine vigorously. This will produce more vigorous vibrations, possibly hitting other atoms and making them move faster, so they can pass the critical point and hit other carbon atoms. Their continuous vibration causes other atoms to vibrate together, and a terrible disaster occurs. One atom after another vibrates faster and faster, combining vigorously, and everything changes. This "disaster" is fire. This is one way to describe "fire." This collision is constantly happening, never stopping. Once it starts, it continues to do so. The heat produced gives other atoms the ability to collide and produce more heat, causing more atoms to behave the same way. So this vigorous combination triggers a lot of vibration.

If I place those less energetic atoms over there, for example, if I place a cup of cold coffee next to a pile of burning wood. The atoms in the coffee will vibrate vigorously, that's the heat of the fire. Of course, there will be... See, this is what happens when you start thinking, you can't stop at all. You just want to know how it started. Why did the wood stay with the oxygen for so long without fire appearing before? Where did this heat come from? Actually, it comes from the tree. The substance of the tree is carbon. Where did that carbon come from? It comes from carbon dioxide in the air. People look at trees and think trees grow from the ground. Plants grow from the ground. But if you ask where the substance of the tree comes from, think carefully about where it comes from. Does the tree come from the air? Of course, trees do come from the air. Carbon dioxide in the air enters the tree, changes, kicks out oxygen atoms, forming oxygen and releasing it, leaving carbon atoms. Carbon and water form the substance of the tree. Water comes from the ground, and carbon atoms enter the tree from the air, right? It comes from the sky. Therefore, almost all trees come from the ground. Sorry, I misspoke, they all come from the air. Of course, a small amount comes from underground minerals, etc.

Of course, I told you oxygen atoms... Oxygen atoms and carbon atoms combine very tightly. So how does the tree cleverly absorb carbon dioxide? At this point, the carbon atoms and oxygen atoms are tightly bound, yet the tree can easily break them down? Ah! Life, is it some mysterious power of life? Wrong, it's the sun's rays. Sunlight shines in and separates the oxygen atoms and carbon atoms. Therefore, sunlight is needed for plants to grow. So the role of the sun is to continuously separate oxygen atoms and carbon atoms. Oxygen, as a kind of bad byproduct, is released into the air, leaving behind carbon atoms and water, which form the substance of the tree. Then we put the substance of the tree in the fireplace. The oxygen produced by the tree wants to combine with the carbon in the tree again. Once you heat it to trigger their combination, the whole process will continue. During their vigorous combination, intense thermal motion will occur. Thus, beautiful light and other things appear. It's as if nothing happened; you've turned oxygen and carbon back into carbon dioxide. But light and heat are produced, which are actually the light and heat of the sun radiating in. So when you light a piece of wood, it's like releasing the sun stored in the wood.

The next question is, why is the sun so active and so hot? I'll stop here and leave you with a question to imagine. Most elastic things, like steel bars or springs, are due to forces related to electricity pulling them back. When you bend something, you're pulling the atoms a little farther apart, so these atoms try to come back together. But a rubber band works differently. There are some long chain-like molecules, and some small molecules that are constantly vibrating and hitting these chain molecules. And the chain molecules are all twisted and funny shapes. When you straighten the rubber band, the chain molecules straighten out. But these chain molecules are constantly being hit from the sides. Other atoms try to twist them, making them contract. Therefore, the rubber band tries to contract. It contracts simply due to heat. So if you heat a rubber band, it will contract more. For example, if you hang a heavy object with a rubber band and then bring a lit match close to the rubber band, it's quite interesting to watch the heavy object rise as the rubber band is heated.

You can also prove this point in another way. To prove that it is indeed heat that drives the contraction of a rubber band. When you stretch a rubber band, it's like compressing the piston and internal gas downwards. If you stretch a rubber band, the stretched chain molecules hit other molecules, making them move faster, so the temperature rises. And when you contract the rubber band, the molecules lose some energy when they hit the chain molecules. It's like hitting something soft; it sinks in and "bang bang." Energy is lost. When you pull the piston out, the atoms hit it and their speed decreases, so the temperature drops. So when a gas expands, its temperature decreases.

The interesting thing is that all the phenomena you observe in this world, such as your gas compressing and heating up, expanding and cooling down, or water evaporating from a cup if it's not covered. All these phenomena can be understood using a simple atomic picture. Thinking this way is very interesting. I don't want to take this kind of thinking too seriously. I think we should imagine happily, without any worries. There won't be a teacher asking questions at the end, otherwise it's an annoying subject.

Different atoms want to be close to each other to varying degrees. For example, oxygen atoms in the air want to be close to carbon atoms. If they get too close, they combine vigorously. If they are not very close, they repel each other and separate. So they don't know they can combine. It's like a ball trying to climb a hill. There's a hole in front of it, into which it can fall, like a crater. A deep opening. The ball just circles around it and doesn't fall in. Because when the ball starts to climb the slope, it rolls back. But if you make it go fast enough to pass the critical point, it will fall into the hole. So if something like wood comes into contact with oxygen, and there are carbon atoms in the wood. The oxygen atoms come and hit the carbon atoms, but the temperature isn't high enough. The oxygen atoms run away again. Air always comes and goes, and nothing happens.

If you heat the oxygen atoms in some way to make them faster, to accelerate a few atoms at first, meaning to get them past the critical point. They get close enough to the carbon atoms, and then they combine vigorously. This will produce more vigorous vibrations, possibly hitting other atoms and making them move faster, so they can pass the critical point and hit other carbon atoms. Their continuous vibration causes other atoms to vibrate together, and a terrible disaster occurs. One atom after another vibrates faster and faster, combining vigorously, and everything changes. This "disaster" is fire. This is one way to describe "fire." This collision is constantly happening, never stopping. Once it starts, it continues to do so. The heat produced gives other atoms the ability to collide and produce more heat, causing more atoms to behave the same way. So this vigorous combination triggers a lot of vibration.

If I place those less energetic atoms over there, for example, if I place a cup of cold coffee next to a pile of burning wood. The atoms in the coffee will vibrate vigorously, that's the heat of the fire. Of course, there will be... See, this is what happens when you start thinking, you can't stop at all. You just want to know how it started. Why did the wood stay with the oxygen for so long without fire appearing before? Where did this heat come from? Actually, it comes from the tree. The substance of the tree is carbon. Where did that carbon come from? It comes from carbon dioxide in the air. People look at trees and think trees grow from the ground. Plants grow from the ground. But if you ask where the substance of the tree comes from, think carefully about where it comes from. Does the tree come from the air? Of course, trees do come from the air. Carbon dioxide in the air enters the tree, changes, kicks out oxygen atoms, forming oxygen and releasing it, leaving carbon atoms. Carbon and water form the substance of the tree. Water comes from the ground, and carbon atoms enter the tree from the air, right? It comes from the sky. Therefore, almost all trees come from the ground. Sorry, I misspoke, they all come from the air. Of course, a small amount comes from underground minerals, etc.

Of course, I told you oxygen atoms... Oxygen atoms and carbon atoms combine very tightly. So how does the tree cleverly absorb carbon dioxide? At this point, the carbon atoms and oxygen atoms are tightly bound, yet the tree can easily break them down? Ah! Life, is it some mysterious power of life? Wrong, it's the sun's rays. Sunlight shines in and separates the oxygen atoms and carbon atoms. Therefore, sunlight is needed for plants to grow. So the role of the sun is to continuously separate oxygen atoms and carbon atoms. Oxygen, as a kind of bad byproduct, is released into the air, leaving behind carbon atoms and water, which form the substance of the tree. Then we put the substance of the tree in the fireplace. The oxygen produced by the tree wants to combine with the carbon in the tree again. Once you heat it to trigger their combination, the whole process will continue. During their vigorous combination, intense thermal motion will occur. Thus, beautiful light and other things appear. It's as if nothing happened; you've turned oxygen and carbon back into carbon dioxide. But light and heat are produced, which are actually the light and heat of the sun radiating in. So when you light a piece of wood, it's like releasing the sun stored in the wood.

The next question is, why is the sun so active and so hot? I'll stop here and leave you with a question to imagine. Most elastic things, like steel bars or springs, are due to forces related to electricity pulling them back. When you bend something, you're pulling the atoms a little farther apart, so these atoms try to come back together. But a rubber band works differently. There are some long chain-like molecules, and some small molecules that are constantly vibrating and hitting these chain molecules. And the chain molecules are all twisted and funny shapes. When you straighten the rubber band, the chain molecules straighten out. But these chain molecules are constantly being hit from the sides. Other atoms try to twist them, making them contract. Therefore, the rubber band tries to contract. It contracts simply due to heat. So if you heat a rubber band, it will contract more. For example, if you hang a heavy object with a rubber band and then bring a lit match close to the rubber band, it's quite interesting to watch the heavy object rise as the rubber band is heated.

You can also prove this point in another way. To prove that it is indeed heat that drives the contraction of a rubber band. When you stretch a rubber band, it's like compressing the piston and internal gas downwards. If you stretch a rubber band, the stretched chain molecules hit other molecules, making them move faster, so the temperature rises. And when you contract the rubber band, the molecules lose some energy when they hit the chain molecules. It's like hitting something soft; it sinks in and "bang bang." Energy is lost. When you pull the piston out, the atoms hit it and their speed decreases, so the temperature drops. So when a gas expands, its temperature decreases.

The interesting thing is that all the phenomena you observe in this world, such as your gas compressing and heating up, expanding and cooling down, or water evaporating from a cup if it's not covered. All these phenomena can be understood using a simple atomic picture. Thinking this way is very interesting. I don't want to take this kind of thinking too seriously. I think we should imagine happily, without any worries. There won't be a teacher asking questions at the end, otherwise it's an annoying subject.

Different atoms want to be close to each other to varying degrees. For example, oxygen atoms in the air want to be close to carbon atoms. If they get too close, they combine vigorously. If they are not very close, they repel each other and separate. So they don't know they can combine. It's like a ball trying to climb a hill. There's a hole in front of it, into which it can fall, like a crater. A deep opening. The ball just circles around it and doesn't fall in. Because when the ball starts to climb the slope, it rolls back. But if you make it go fast enough to pass the critical point, it will fall into the hole. So if something like wood comes into contact with oxygen, and there are carbon atoms in the wood. The oxygen atoms come and hit the carbon atoms, but the temperature isn't high enough. The oxygen atoms run away again. Air always comes and goes, and nothing happens.

If you heat the oxygen atoms in some way to make them faster, to accelerate a few atoms at first, meaning to get them past the critical point. They get close enough to the carbon atoms, and then they combine vigorously. This will produce more vigorous vibrations, possibly hitting other atoms and making them move faster, so they can pass the critical point and hit other carbon atoms. Their continuous vibration causes other atoms to vibrate together, and a terrible disaster occurs. One atom after another vibrates faster and faster, combining vigorously, and everything changes. This "disaster" is fire. This is one way to describe "fire." This collision is constantly happening, never stopping. Once it starts, it continues to do so. The heat produced gives other atoms the ability to collide and produce more heat, causing more atoms to behave the same way. So this vigorous combination triggers a lot of vibration.

If I place those less energetic atoms over there, for example, if I place a cup of cold coffee next to a pile of burning wood. The atoms in the coffee will vibrate vigorously, that's the heat of the fire. Of course, there will be... See, this is what happens when you start thinking, you can't stop at all. You just want to know how it started. Why did the wood stay with the oxygen for so long without fire appearing before? Where did this heat come from? Actually, it comes from the tree. The substance of the tree is carbon. Where did that carbon come from? It comes from carbon dioxide in the air. People look at trees and think trees grow from the ground. Plants grow from the ground. But if you ask where the substance of the tree comes from, think carefully about where it comes from. Does the tree come from the air? Of course, trees do come from the air. Carbon dioxide in the air enters the tree, changes, kicks out oxygen atoms, forming oxygen and releasing it, leaving carbon atoms. Carbon and water form the substance of the tree. Water comes from the ground, and carbon atoms enter the tree from the air, right? It comes from the sky. Therefore, almost all trees come from the ground. Sorry, I misspoke, they all come from the air. Of course, a small amount comes from underground minerals, etc.

Of course, I told you oxygen atoms... Oxygen atoms and carbon atoms combine very tightly. So how does the tree cleverly absorb carbon dioxide? At this point, the carbon atoms and oxygen atoms are tightly bound, yet the tree can easily break them down? Ah! Life, is it some mysterious power of life? Wrong, it's the sun's rays. Sunlight shines in and separates the oxygen atoms and carbon atoms. Therefore, sunlight is needed for plants to grow. So the role of the sun is to continuously separate oxygen atoms and carbon atoms. Oxygen, as a kind of bad byproduct, is released into the air, leaving behind carbon atoms and water, which form the substance of the tree. Then we put the substance of the tree in the fireplace. The oxygen produced by the tree wants to combine with the carbon in the tree again. Once you heat it to trigger their combination, the whole process will continue. During their vigorous combination, intense thermal motion will occur. Thus, beautiful light and other things appear. It's as if nothing happened; you've turned oxygen and carbon back into carbon dioxide. But light and heat are produced, which are actually the light and heat of the sun radiating in. So when you light a piece of wood, it's like releasing the sun stored in the wood.

The next question is, why is the sun so active and so hot? I'll stop here and leave you with a question to imagine. Most elastic things, like steel bars or springs, are due to forces related to electricity pulling them back. When you bend something, you're pulling the atoms a little farther apart, so these atoms try to come back together. But a rubber band works differently. There are some long chain-like molecules, and some small molecules that are constantly vibrating and hitting these chain molecules. And the chain molecules are all twisted and funny shapes. When you straighten the rubber band, the chain molecules straighten out. But these chain molecules are constantly being hit from the sides. Other atoms try to twist them, making them contract. Therefore, the rubber band tries to contract. It contracts simply due to heat. So if you heat a rubber band, it will contract more. For example, if you hang a heavy object with a rubber band and then bring a lit match close to the rubber band, it's quite interesting to watch the heavy object rise as the rubber band is heated.

You can also prove this point in another way. To prove that it is indeed heat that drives the contraction of a rubber band. When you stretch a rubber band, it's like compressing the piston and internal gas downwards. If you stretch a rubber band, the stretched chain molecules hit other molecules, making them move faster, so the temperature rises. And when you contract the rubber band, the molecules lose some energy when they hit the chain molecules. It's like hitting something soft; it sinks in and "bang bang." Energy is lost. When you pull the piston out, the atoms hit it and their speed decreases, so the temperature drops. So when a gas expands, its temperature decreases.

The interesting thing is that all the phenomena you observe in this world, such as your gas compressing and heating up, expanding and cooling down, or water evaporating from a cup if it's not covered. All these phenomena can be understood using a simple atomic picture. Thinking this way is very interesting. I don't want to take this kind of thinking too seriously. I think we should imagine happily, without any worries. There won't be a teacher asking questions at the end, otherwise it's an annoying subject.

Different atoms want to be close to each other to varying degrees. For example, oxygen atoms in the air want to be close to carbon atoms. If they get too close, they combine vigorously. If they are not very close, they repel each other and separate. So they don't know they can combine. It's like a ball trying to climb a hill. There's a hole in front of it, into which it can fall, like a crater. A deep opening. The ball just circles around it and doesn't fall in. Because when the ball starts to climb the slope, it rolls back. But if you make it go fast enough to pass the critical point, it will fall into the hole. So if something like wood comes into contact with oxygen, and there are carbon atoms in the wood. The oxygen atoms come and hit the carbon atoms, but the temperature isn't high enough. The oxygen atoms run away again. Air always comes and goes, and nothing happens.

If you heat the oxygen atoms in some way to make them faster, to accelerate a few atoms at first, meaning to get them past the critical point. They get close enough to the carbon atoms, and then they combine vigorously. This will produce more vigorous vibrations, possibly hitting other atoms and making them move faster, so they can pass the critical point and hit other carbon atoms. Their continuous vibration causes other atoms to vibrate together, and a terrible disaster occurs. One atom after another vibrates faster and faster, combining vigorously, and everything changes. This "disaster" is fire. This is one way to describe "fire." This collision is constantly happening, never stopping. Once it starts, it continues to do so. The heat produced gives other atoms the ability to collide and produce more heat, causing more atoms to behave the same way. So this vigorous combination triggers a lot of vibration.

If I place those less energetic atoms over there, for example, if I place a cup of cold coffee next to a pile of burning wood. The atoms in the coffee will vibrate vigorously, that's the heat of the fire. Of course, there will be... See, this is what happens when you start thinking, you can't stop at all. You just want to know how it started. Why did the wood stay with the oxygen for so long without fire appearing before? Where did this heat come from? Actually, it comes from the tree. The substance of the tree is carbon. Where did that carbon come from? It comes from carbon dioxide in the air. People look at trees and think trees grow from the ground. Plants grow from the ground. But if you ask where the substance of the tree comes from, think carefully about where it comes from. Does the tree come from the air? Of course, trees do come from the air. Carbon dioxide in the air enters the tree, changes, kicks out oxygen atoms, forming oxygen and releasing it, leaving carbon atoms. Carbon and water form the substance of the tree. Water comes from the ground, and carbon atoms enter the tree from the air, right? It comes from the sky. Therefore, almost all trees come from the ground. Sorry, I misspoke, they all come from the air. Of course, a small amount comes from underground minerals, etc.

Of course, I told you oxygen atoms... Oxygen atoms and carbon atoms combine very tightly. So how does the tree cleverly absorb carbon dioxide? At this point, the carbon atoms and oxygen atoms are tightly bound, yet the tree can easily break them down? Ah! Life, is it some mysterious power of life? Wrong, it's the sun's rays. Sunlight shines in and separates the oxygen atoms and carbon atoms. Therefore, sunlight is needed for plants to grow. So the role of the sun is to continuously separate oxygen atoms and carbon atoms. Oxygen, as a kind of bad byproduct, is released into the air, leaving behind carbon atoms and water, which form the substance of the tree. Then we put the substance of the tree in the fireplace. The oxygen produced by the tree wants to combine with the carbon in the tree again. Once you heat it to trigger their combination, the whole process will continue. During their vigorous combination, intense thermal motion will occur. Thus, beautiful light and other things appear. It's as if nothing happened; you've turned oxygen and carbon back into carbon dioxide. But light and heat are produced, which are actually the light and heat of the sun radiating in. So when you light a piece of wood, it's like releasing the sun stored in the wood.

The next question is, why is the sun so active and so hot? I'll stop here and leave you with a question to imagine. Most elastic things, like steel bars or springs, are due to forces related to electricity pulling them back. When you bend something, you're pulling the atoms a little farther apart, so these atoms try to come back together. But a rubber band works differently. There are some long chain-like molecules, and some small molecules that are constantly vibrating and hitting these chain molecules. And the chain molecules are all twisted and funny shapes. When you straighten the rubber band, the chain molecules straighten out. But these chain molecules are constantly being hit from the sides. Other atoms try to twist them, making them contract. Therefore, the rubber band tries to contract. It contracts simply due to heat. So if you heat a rubber band, it will contract more. For example, if you hang a heavy object with a rubber band and then bring a lit match close to the rubber band, it's quite interesting to watch the heavy object rise as the rubber band is heated.

You can also prove this point in another way. To prove that it is indeed heat that drives the contraction of a rubber band. When you stretch a rubber band, it's like compressing the piston and internal gas downwards. If you stretch a rubber band, the stretched chain molecules hit other molecules, making them move faster, so the temperature rises. And when you contract the rubber band, the molecules lose some energy when they hit the chain molecules. It's like hitting something soft; it sinks in and "bang bang." Energy is lost. When you pull the piston out, the atoms hit it and their speed decreases, so the temperature drops. So when a gas expands, its temperature decreases.

The interesting thing is that all the phenomena you observe in this world, such as your gas compressing and heating up, expanding and cooling down, or water evaporating from a cup if it's not covered. All these phenomena can be understood using a simple atomic picture. Thinking this way is very interesting. I don't want to take this kind of thinking too seriously. I think we should imagine happily, without any worries. There won't be a teacher asking questions at the end, otherwise it's an annoying subject.

Different atoms want to be close to each other to varying degrees. For example, oxygen atoms in the air want to be close to carbon atoms. If they get too close, they combine vigorously. If they are not very close, they repel each other and separate. So they don't know they can combine. It's like a ball trying to climb a hill. There's a hole in front of it, into which it can fall, like a crater. A deep opening. The ball just circles around it and doesn't fall in. Because when the ball starts to climb the slope, it rolls back. But if you make it go fast enough to pass the critical point, it will fall into the hole. So if something like wood comes into contact with oxygen, and there are carbon atoms in the wood. The oxygen atoms come and hit the carbon atoms, but the temperature isn't high enough. The oxygen atoms run away again. Air always comes and goes, and nothing happens.

If you heat the oxygen atoms in some way to make them faster, to accelerate a few atoms at first, meaning to get them past the critical point. They get close enough to the carbon atoms, and then they combine vigorously. This will produce more vigorous vibrations, possibly hitting other atoms and making them move faster, so they can pass the critical point and hit other carbon atoms. Their continuous vibration causes other atoms to vibrate together, and a terrible disaster occurs. One atom after another vibrates faster and faster, combining vigorously, and everything changes. This "disaster" is fire. This is one way to describe "fire." This collision is constantly happening, never stopping. Once it starts, it continues to do so. The heat produced gives other atoms the ability to collide and produce more heat, causing more atoms to behave the same way. So this vigorous combination triggers a lot of vibration.

If I place those less energetic atoms over there, for example, if I place a cup of cold coffee next to a pile of burning wood. The atoms in the coffee will vibrate vigorously, that's the heat of the fire. Of course, there will be... See, this is what happens when you start thinking, you can't stop at all. You just want to know how it started. Why did the wood stay with the oxygen for so long without fire appearing before? Where did this heat come from? Actually, it comes from the tree. The substance of the tree is carbon. Where did that carbon come from? It comes from carbon dioxide in the air. People look at trees and think trees grow from the ground. Plants grow from the ground. But if you ask where the substance of the tree comes from, think carefully about where it comes from. Does the tree come from the air? Of course, trees do come from the air. Carbon dioxide in the air enters the tree, changes, kicks out oxygen atoms, forming oxygen and releasing it, leaving carbon atoms. Carbon and water form the substance of the tree. Water comes from the ground, and carbon atoms enter the tree from the air, right? It comes from the sky. Therefore, almost all trees come from the ground. Sorry, I misspoke, they all come from the air. Of course, a small amount comes from underground minerals, etc.

Of course, I told you oxygen atoms... Oxygen atoms and carbon atoms combine very tightly. So how does the tree cleverly absorb carbon dioxide? At this point, the carbon atoms and oxygen atoms are tightly bound, yet the tree can easily break them down? Ah! Life, is it some mysterious power of life? Wrong, it's the sun's rays. Sunlight shines in and separates the oxygen atoms and carbon atoms. Therefore, sunlight is needed for plants to grow. So the role of the sun is to continuously separate oxygen atoms and carbon atoms. Oxygen, as a kind of bad byproduct, is released into the air, leaving behind carbon atoms and water, which form the substance of the tree. Then we put the substance of the tree in the fireplace. The oxygen produced by the tree wants to combine with the carbon in the tree again. Once you heat it to trigger their combination, the whole process will continue. During their vigorous combination, intense thermal motion will occur. Thus, beautiful light and other things appear. It's as if nothing happened; you've turned oxygen and carbon back into carbon dioxide. But light and heat are produced, which are actually the light and heat of the sun radiating in. So when you light a piece of wood, it's like releasing the sun stored in the wood.

The next question is, why is the sun so active and so hot? I'll stop here and leave you with a question to imagine. Most elastic things, like steel bars or springs, are due to forces related to electricity pulling them back. When you bend something, you're pulling the atoms a little farther apart, so these atoms try to come back together. But a rubber band works differently. There are some long chain-like molecules, and some small molecules that are constantly vibrating and hitting these chain molecules. And the chain molecules are all twisted and funny shapes. When you straighten the rubber band, the chain molecules straighten out. But these chain molecules are constantly being hit from the sides. Other atoms try to twist them, making them contract. Therefore, the rubber band tries to contract. It contracts simply due to heat. So if you heat a rubber band, it will contract more. For example, if you hang a heavy object with a rubber band and then bring a lit match close to the rubber band, it's quite interesting to watch the heavy object rise as the rubber band is heated.

You can also prove this point in another way. To prove that it is indeed heat that drives the contraction of a rubber band. When you stretch a rubber band, it's like compressing the piston and internal gas downwards. If you stretch a rubber band, the stretched chain molecules hit other molecules, making them move faster, so the temperature rises. And when you contract the rubber band, the molecules lose some energy when they hit the chain molecules. It's like hitting something soft; it sinks in and "bang bang." Energy is lost. When you pull the piston out, the atoms hit it and their speed decreases, so the temperature drops. So when a gas expands, its temperature decreases.

The interesting thing is that all the phenomena you observe in this world, such as your gas compressing and heating up, expanding and cooling down, or water evaporating from a cup if it's not covered. All these phenomena can be understood using a simple atomic picture. Thinking this way is very interesting. I don't want to take this kind of thinking too seriously. I think we should imagine happily, without any worries. There won't be a teacher asking questions at the end, otherwise it's an annoying subject.

Different atoms want to be close to each other to varying degrees. For example, oxygen atoms in the air want to be close to carbon atoms. If they get too close, they combine vigorously. If they are not very close, they repel each other and separate. So they don't know they can combine. It's like a ball trying to climb a hill. There's a hole in front of it, into which it can fall, like a crater. A deep opening. The ball just circles around it and doesn't fall in. Because when the ball starts to climb the slope, it rolls back. But if you make it go fast enough to pass the critical point, it will fall into the hole. So if something like wood comes into contact with oxygen, and there are carbon atoms in the wood. The oxygen atoms come and hit the carbon atoms, but the temperature isn't high enough. The oxygen atoms run away again. Air always comes and goes, and nothing happens.

If you heat the oxygen atoms in some way to make them faster, to accelerate a few atoms at first, meaning to get them past the critical point. They get close enough to the carbon atoms, and then they combine vigorously. This will produce more vigorous vibrations, possibly hitting other atoms and making them move faster, so they can pass the critical point and hit other carbon atoms. Their continuous vibration causes other atoms to vibrate together, and a terrible disaster occurs. One atom after another vibrates faster and faster, combining vigorously, and everything changes. This "disaster" is fire. This is one way to describe "fire." This collision is constantly happening, never stopping. Once it starts, it continues to do so. The heat produced gives other atoms the ability to collide and produce more heat, causing more atoms to behave the same way. So this vigorous combination triggers a lot of vibration.

If I place those less energetic atoms over there, for example, if I place a cup of cold coffee next to a pile of burning wood. The atoms in the coffee will vibrate vigorously, that's the heat of the fire. Of course, there will be... See, this is what happens when you start thinking, you can't stop at all. You just want to know how it started. Why did the wood stay with the oxygen for so long without fire appearing before? Where did this heat come from? Actually, it comes from the tree. The substance of the tree is carbon. Where did that carbon come from? It comes from carbon dioxide in the air. People look at trees and think trees grow from the ground. Plants grow from the ground. But if you ask where the substance of the tree comes from, think carefully about where it comes from. Does the tree come from the air? Of course, trees do come from the air. Carbon dioxide in the air enters the tree, changes, kicks out oxygen atoms, forming oxygen and releasing it, leaving carbon atoms. Carbon and water form the substance of the tree. Water comes from the ground, and carbon atoms enter the tree from the air, right? It comes from the sky. Therefore, almost all trees come from the ground. Sorry, I misspoke, they all come from the air. Of course, a small amount comes from underground minerals, etc.

Of course, I told you oxygen atoms... Oxygen atoms and carbon atoms combine very tightly. So how does the tree cleverly absorb carbon dioxide? At this point, the carbon atoms and oxygen atoms are tightly bound, yet the tree can easily break them down? Ah! Life, is it some mysterious power of life? Wrong, it's the sun's rays. Sunlight shines in and separates the oxygen atoms and carbon atoms. Therefore, sunlight is needed for plants to grow. So the role of the sun is to continuously separate oxygen atoms and carbon atoms. Oxygen, as a kind of bad byproduct, is released into the air, leaving behind carbon atoms and water, which form the substance of the tree. Then we put the substance of the tree in the fireplace. The oxygen produced by the tree wants to combine with the carbon in the tree again. Once you heat it to trigger their combination, the whole process will continue. During their vigorous combination, intense thermal motion will occur. Thus, beautiful light and other things appear. It's as if nothing happened; you've turned oxygen and carbon back into carbon dioxide. But light and heat are produced, which are actually the light and heat of the sun radiating in. So when you light a piece of wood, it's like releasing the sun stored in the wood.

The next question is, why is the sun so active and so hot? I'll stop here and leave you with a question to imagine. Most elastic things, like steel bars or springs, are due to forces related to electricity pulling them back. When you bend something, you're pulling the atoms a little farther apart, so these atoms try to come back together. But a rubber band works differently. There are some long chain-like molecules, and some small molecules that are constantly vibrating and hitting these chain molecules. And the chain molecules are all twisted and funny shapes. When you straighten the rubber band, the chain molecules straighten out. But these chain molecules are constantly being hit from the sides. Other atoms try to twist them, making them contract. Therefore, the rubber band tries to contract. It contracts simply due to heat. So if you heat a rubber band, it will contract more. For example, if you hang a heavy object with a rubber band and then bring a lit match close to the rubber band, it's quite interesting to watch the heavy object rise as the rubber band is heated.

You can also prove this point in another way. To prove that it is indeed heat that drives the contraction of a rubber band. When you stretch a rubber band, it's like compressing the piston and internal gas downwards. If you stretch a rubber band, the stretched chain molecules hit other molecules, making them move faster, so the temperature rises. And when you contract the rubber band, the molecules lose some energy when they hit the chain molecules. It's like hitting something soft; it sinks in and "bang bang." Energy is lost. When you pull the piston out, the atoms hit it and their speed decreases, so the temperature drops. So when a gas expands, its temperature decreases.

The interesting thing is that all the phenomena you observe in this world, such as your gas compressing and heating up, expanding and cooling down, or water evaporating from a cup if it's not covered. All these phenomena can be understood using a simple atomic picture. Thinking this way is very interesting. I don't want to take this kind of thinking too seriously. I think we should imagine happily, without any worries. There won't be a teacher asking questions at the end, otherwise it's an annoying subject.

Different atoms want to be close to each other to varying degrees. For example, oxygen atoms in the air want to be close to carbon atoms. If they get too close, they combine vigorously. If they are not very close, they repel each other and separate. So they don't know they can combine. It's like a ball trying to climb a hill. There's a hole in front of it, into which it can fall, like a crater. A deep opening. The ball just circles around it and doesn't fall in. Because when the ball starts to climb the slope, it rolls back. But if you make it go fast enough to pass the critical point, it will fall into the hole. So if something like wood comes into contact with oxygen, and there are carbon atoms in the wood. The oxygen atoms come and hit the carbon atoms, but the temperature isn't high enough. The oxygen atoms run away again. Air always comes and goes, and nothing happens.

If you heat the oxygen atoms in some way to make them faster, to accelerate a few atoms at first, meaning to get them past the critical point. They get close enough to the carbon atoms, and then they combine vigorously. This will produce more vigorous vibrations, possibly hitting other atoms and making them move faster, so they can pass the critical point and hit other carbon atoms. Their continuous vibration causes other atoms to vibrate together, and a terrible disaster occurs. One atom after another vibrates faster and faster, combining vigorously, and everything changes. This "disaster" is fire. This is one way to describe "fire." This collision is constantly happening, never stopping. Once it starts, it continues to do so. The heat produced gives other atoms the ability to collide and produce more heat, causing more atoms to behave the same way. So this vigorous combination triggers a lot of vibration.

If I place those less energetic atoms over there, for example, if I place a cup of cold coffee next to a pile of burning wood. The atoms in the coffee will vibrate vigorously, that's the heat of the fire. Of course, there will be... See, this is what happens when you start thinking, you can't stop at all. You just want to know how it started. Why did the wood stay with the oxygen for so long without fire appearing before? Where did this heat come from? Actually, it comes from the tree. The substance of the tree is carbon. Where did that carbon come from? It comes from carbon dioxide in the air. People look at trees and think trees grow from the ground. Plants grow from the ground. But if you ask where the substance of the tree comes from, think carefully about where it comes from. Does the tree come from the air? Of course, trees do come from the air. Carbon dioxide in the air enters the tree, changes, kicks out oxygen atoms, forming oxygen and releasing it, leaving carbon atoms. Carbon and water form the substance of the tree. Water comes from the ground, and carbon atoms enter the tree from the air, right? It comes from the sky. Therefore, almost all trees come from the ground. Sorry, I misspoke, they all come from the air. Of course, a small amount comes from underground minerals, etc.

Of course, I told you oxygen atoms... Oxygen atoms and carbon atoms combine very tightly. So how does the tree cleverly absorb carbon dioxide? At this point, the carbon atoms and oxygen atoms are tightly bound, yet the tree can easily break them down? Ah! Life, is it some mysterious power of life? Wrong, it's the sun's rays. Sunlight shines in and separates the oxygen atoms and carbon atoms. Therefore, sunlight is needed for plants to grow. So the role of the sun is to continuously separate oxygen atoms and carbon atoms. Oxygen, as a kind of bad byproduct, is released into the air, leaving behind carbon atoms and water, which form the substance of the tree. Then we put the substance of the tree in the fireplace. The oxygen produced by the tree wants to combine with the carbon in the tree again. Once you heat it to trigger their combination, the whole process will continue. During their vigorous combination, intense thermal motion will occur. Thus, beautiful light and other things appear. It's as if nothing happened; you've turned oxygen and carbon back into carbon dioxide. But light and heat are produced, which are actually the light and heat of the sun radiating in. So when you light a piece of wood, it's like releasing the sun stored in the wood.

The next question is, why is the sun so active and so hot? I'll stop here and leave you with a question to imagine. Most elastic things, like steel bars or springs, are due to forces related to electricity pulling them back. When you bend something, you're pulling the atoms a little farther apart, so these atoms try to come back together. But a rubber band works differently. There are some long chain-like molecules, and some small molecules that are constantly vibrating and hitting these chain molecules. And the chain molecules are all twisted and funny shapes. When you straighten the rubber band, the chain molecules straighten out. But these chain molecules are constantly being hit from the sides. Other atoms try to twist them, making them contract. Therefore, the rubber band tries to contract. It contracts simply due to heat. So if you heat a rubber band, it will contract more. For example, if you hang a heavy object with a rubber band and then bring a lit match close to the rubber band, it's quite interesting to watch the heavy object rise as the rubber band is heated.

You can also prove this point in another way. To prove that it is indeed heat that drives the contraction of a rubber band. When you stretch a rubber band, it's like compressing the piston and internal gas downwards. If you stretch a rubber band, the stretched chain molecules hit other molecules, making them move faster, so the temperature rises. And when you contract the rubber band, the molecules lose some energy when they hit the chain molecules. It's like hitting something soft; it sinks in and "bang bang." Energy is lost. When you pull the piston out, the atoms hit it and their speed decreases, so the temperature drops. So when a gas expands, its temperature decreases.

The interesting thing is that all the phenomena you observe in this world, such as your gas compressing and heating up, expanding and cooling down, or water evaporating from a cup if it's not covered. All these phenomena can be understood using a simple atomic picture. Thinking this way is very interesting. I don't want to take this kind of thinking too seriously. I think we should imagine happily, without any worries. There won't be a teacher asking questions at the end, otherwise it's an annoying subject.

Different atoms want to be close to each other to varying degrees. For example, oxygen atoms in the air want to be close to carbon atoms. If they get too close, they combine vigorously. If they are not very close, they repel each other and separate. So they don't know they can combine. It's like a ball trying to climb a hill. There's a hole in front of it, into which it can fall, like a crater. A deep opening. The ball just circles around it and doesn't fall in. Because when the ball starts to climb the slope, it rolls back. But if you make it go fast enough to pass the critical point, it will fall into the hole. So if something like wood comes into contact with oxygen, and there are carbon atoms in the wood. The oxygen atoms come and hit the carbon atoms, but the temperature isn't high enough. The oxygen atoms run away again. Air always comes and goes, and nothing happens.

If you heat the oxygen atoms in some way to make them faster, to accelerate a few atoms at first, meaning to get them past the critical point. They get close enough to the carbon atoms, and then they combine vigorously. This will produce more vigorous vibrations, possibly hitting other atoms and making them move faster, so they can pass the critical point and hit other carbon atoms. Their continuous vibration causes other atoms to vibrate together, and a terrible disaster occurs. One atom after another vibrates faster and faster, combining vigorously, and everything changes. This "disaster" is fire. This is one way to describe "fire." This collision is constantly happening, never stopping. Once it starts, it continues to do so. The heat produced gives other atoms the ability to collide and produce more heat, causing more atoms to behave the same way. So this vigorous combination triggers a lot of vibration.

If I place those less energetic atoms over there, for example, if I place a cup of cold coffee next to a pile of burning wood. The atoms in the coffee will vibrate vigorously, that's the heat of the fire. Of course, there will be... See, this is what happens when you start thinking, you can't stop at all. You just want to know how it started. Why did the wood stay with the oxygen for so long without fire appearing before? Where did this heat come from? Actually, it comes from the tree. The substance of the tree is carbon. Where did that carbon come from? It comes from carbon dioxide in the air. People look at trees and think trees grow from the ground. Plants grow from the ground. But if you ask where the substance of the tree comes from, think carefully about where it comes from. Does the tree come from the air? Of course, trees do come from the air. Carbon dioxide in the air enters the tree, changes, kicks out oxygen atoms, forming oxygen and releasing it, leaving carbon atoms. Carbon and water form the substance of the tree. Water comes from the ground, and carbon atoms enter the tree from the air, right? It comes from the sky. Therefore, almost all trees come from the ground. Sorry, I misspoke, they all come from the air. Of course, a small amount comes from underground minerals, etc.

Of course, I told you oxygen atoms... Oxygen atoms and carbon atoms combine very tightly. So how does the tree cleverly absorb carbon dioxide? At this point, the carbon atoms and oxygen atoms are tightly bound, yet the tree can easily break them down? Ah! Life, is it some mysterious power of life? Wrong, it's the sun's rays. Sunlight shines in and separates the oxygen atoms and carbon atoms. Therefore, sunlight is needed for plants to grow. So the role of the sun is to continuously separate oxygen atoms and carbon atoms. Oxygen, as a kind of bad byproduct, is released into the air, leaving behind carbon atoms and water, which form the substance of the tree. Then we put the substance of the tree in the fireplace. The oxygen produced by the tree wants to combine with the carbon in the tree again. Once you heat it to trigger their combination, the whole process will continue. During their vigorous combination, intense thermal motion will occur. Thus, beautiful light and other things appear. It's as if nothing happened; you've turned oxygen and carbon back into carbon dioxide. But light and heat are produced, which are actually the light and heat of the sun radiating in. So when you light a piece of wood, it's like releasing the sun stored in the wood.

The next question is, why is the sun so active and so hot? I'll stop here and leave you with a question to imagine. Most elastic things, like steel bars or springs, are due to forces related to electricity pulling them back. When you bend something, you're pulling the atoms a little farther apart, so these atoms try to come back together. But a rubber band works differently. There are some long chain-like molecules, and some small molecules that are constantly vibrating and hitting these chain molecules. And the chain molecules are all twisted and funny shapes. When you straighten the rubber band, the chain molecules straighten out. But these chain molecules are constantly being hit from the sides. Other atoms try to twist them, making them contract. Therefore, the rubber band tries to contract. It contracts simply due to heat. So if you heat a rubber band, it will contract more. For example, if you hang a heavy object with a rubber band and then bring a lit match close to the rubber band, it's quite interesting to watch the heavy object rise as the rubber band is heated.

You can also prove this point in another way. To prove that it is indeed heat that drives the contraction of a rubber band. When you stretch a rubber band, it's like compressing the piston and internal gas downwards. If you stretch a rubber band, the stretched chain molecules hit other molecules, making them move faster, so the temperature rises. And when you contract the rubber band, the molecules lose some energy when they hit the chain molecules. It's like hitting something soft; it sinks in and "bang bang." Energy is lost. When you pull the piston out, the atoms hit it and their speed decreases, so the temperature drops. So when a gas expands, its temperature decreases.

The interesting thing is that all the phenomena you observe in this world, such as your gas compressing and heating up, expanding and cooling down, or water evaporating from a cup if it's not covered. All these phenomena can be understood using a simple atomic picture. Thinking this way is very interesting. I don't want to take this kind of thinking too seriously. I think we should imagine happily, without any worries. There won't be a teacher asking questions at the end, otherwise it's an annoying subject.

Different atoms want to be close to each other to varying degrees. For example, oxygen atoms in the air want to be close to carbon atoms. If they get too close, they combine vigorously. If they are not very close, they repel each other and separate. So they don't know they can combine. It's like a ball trying to climb a hill. There's a hole in front of it, into which it can fall, like a crater. A deep opening. The ball just circles around it and doesn't fall in. Because when the ball starts to climb the slope, it rolls back. But if you make it go fast enough to pass the critical point, it will fall into the hole. So if something like wood comes into contact with oxygen, and there are carbon atoms in the wood. The oxygen atoms come and hit the carbon atoms, but the temperature isn't high enough. The oxygen atoms run away again. Air always comes and goes, and nothing happens.

If you heat the oxygen atoms in some way to make them faster, to accelerate a few atoms at first, meaning to get them past the critical point. They get close enough to the carbon atoms, and then they combine vigorously. This will produce more vigorous vibrations, possibly hitting other atoms and making them move faster, so they can pass the critical point and hit other carbon atoms. Their continuous vibration causes other atoms to vibrate together, and a terrible disaster occurs. One atom after another vibrates faster and faster, combining vigorously, and everything changes. This "disaster" is fire. This is one way to describe "fire." This collision is constantly happening, never stopping. Once it starts, it continues to do so. The heat produced gives other atoms the ability to collide and produce more heat, causing more atoms to behave the same way. So this vigorous combination triggers a lot of vibration.

If I place those less energetic atoms over there, for example, if I place a cup of cold coffee next to a pile of burning wood. The atoms in the coffee will vibrate vigorously, that's the heat of the fire. Of course, there will be... See, this is what happens when you start thinking, you can't stop at all. You just want to know how it started. Why did the wood stay with the oxygen for so long without fire appearing before? Where did this heat come from? Actually, it comes from the tree. The substance of the tree is carbon. Where did that carbon come from? It comes from carbon dioxide in the air. People look at trees and think trees grow from the ground. Plants grow from the ground. But if you ask where the substance of the tree comes from, think carefully about where it comes from. Does the tree come from the air? Of course, trees do come from the air. Carbon dioxide in the air enters the tree, changes, kicks out oxygen atoms, forming oxygen and releasing it, leaving carbon atoms. Carbon and water form the substance of the tree. Water comes from the ground, and carbon atoms enter the tree from the air, right? It comes from the sky. Therefore, almost all trees come from the ground. Sorry, I misspoke, they all come from the air. Of course, a small amount comes from underground minerals, etc.

Of course, I told you oxygen atoms... Oxygen atoms and carbon atoms combine very tightly. So how does the tree cleverly absorb carbon dioxide? At this point, the carbon atoms and oxygen atoms are tightly bound, yet the tree can easily break them down? Ah! Life, is it some mysterious power of life? Wrong, it's the sun's rays. Sunlight shines in and separates the oxygen atoms and carbon atoms. Therefore, sunlight is needed for plants to grow. So the role of the sun is to continuously separate oxygen atoms and carbon atoms. Oxygen, as a kind of bad byproduct, is released into the air, leaving behind carbon atoms and water, which form the substance of the tree. Then we put the substance of the tree in the fireplace. The oxygen produced by the tree wants to combine with the carbon in the tree again. Once you heat it to trigger their combination, the whole process will continue. During their vigorous combination, intense thermal motion will occur. Thus, beautiful light and other things appear. It's as if nothing happened; you've turned oxygen and carbon back into carbon dioxide. But light and heat are produced, which are actually the light and heat of the sun radiating in. So when you light a piece of wood, it's like releasing the sun stored in the wood.

The next question is, why is the sun so active and so hot? I'll stop here and leave you with a question to imagine. Most elastic things, like steel bars or springs, are due to forces related to electricity pulling them back. When you bend something, you're pulling the atoms a little farther apart, so these atoms try to come back together. But a rubber band works differently. There are some long chain-like molecules, and some small molecules that are constantly vibrating and hitting these chain molecules. And the chain molecules are all twisted and funny shapes. When you straighten the rubber band, the chain molecules straighten out. But these chain molecules are constantly being hit from the sides. Other atoms try to twist them, making them contract. Therefore, the rubber band tries to contract. It contracts simply due to heat. So if you heat a rubber band, it will contract more. For example, if you hang a heavy object with a rubber band and then bring a lit match close to the rubber band, it's quite interesting to watch the heavy object rise as the rubber band is heated.

You can also prove this point in another way. To prove that it is indeed heat that drives the contraction of a rubber band. When you stretch a rubber band, it's like compressing the piston and internal gas downwards. If you stretch a rubber band, the stretched chain molecules hit other molecules, making them move faster, so the temperature rises. And when you contract the rubber band, the molecules lose some energy when they hit the chain molecules. It's like hitting something soft; it sinks in and "bang bang." Energy is lost. When you pull the piston out, the atoms hit it and their speed decreases, so the temperature drops. So when a gas expands, its temperature decreases.

The interesting thing is that all the phenomena you observe in this world, such as your gas compressing and heating up, expanding and cooling down, or water evaporating from a cup if it's not covered. All these phenomena can be understood using a simple atomic picture. Thinking this way is very interesting. I don't want to take this kind of thinking too seriously. I think we should imagine happily, without any worries. There won't be a teacher asking questions at the end, otherwise it's an annoying subject.

Different atoms want to be close to each other to varying degrees. For example, oxygen atoms in the air want to be close to carbon atoms. If they get too close, they combine vigorously. If they are not very close, they repel each other and separate. So they don't know they can combine. It's like a ball trying to climb a hill. There's a hole in front of it, into which it can fall, like a crater. A deep opening. The ball just circles around it and doesn't fall in. Because when the ball starts to climb the slope, it rolls back. But if you make it go fast enough to pass the critical point, it will fall into the hole. So if something like wood comes into contact with oxygen, and there are carbon atoms in the wood. The oxygen atoms come and hit the carbon atoms, but the temperature isn't high enough. The oxygen atoms run away again. Air always comes and goes, and nothing happens.

If you heat the oxygen atoms in some way to make them faster, to accelerate a few atoms at first, meaning to get them past the critical point. They get close enough to the carbon atoms, and then they combine vigorously. This will produce more vigorous vibrations, possibly hitting other atoms and making them move faster, so they can pass the critical point and hit other carbon atoms. Their continuous vibration causes other atoms to vibrate together, and a terrible disaster occurs. One atom after another vibrates faster and faster, combining vigorously, and everything changes. This "disaster" is fire. This is one way to describe "fire." This collision is constantly happening, never stopping. Once it starts, it continues to do so. The heat produced gives other atoms the ability to collide and produce more heat, causing more atoms to behave the same way. So this vigorous combination triggers a lot of vibration.

If I place those less energetic atoms over there, for example, if I place a cup of cold coffee next to a pile of burning wood. The atoms in the coffee will vibrate vigorously, that's the heat of the fire. Of course, there will be... See, this is what happens when you start thinking, you can't stop at all. You just want to know how it started. Why did the wood stay with the oxygen for so long without fire appearing before? Where did this heat come from? Actually, it comes from the tree. The substance of the tree is carbon. Where did that carbon come from? It comes from carbon dioxide in the air. People look at trees and think trees grow from the ground. Plants grow from the ground. But if you ask where the substance of the tree comes from, think carefully about where it comes from. Does the tree come from the air? Of course, trees do come from the air. Carbon dioxide in the air enters the tree, changes, kicks out oxygen atoms, forming oxygen and releasing it, leaving carbon atoms. Carbon and water form the substance of the tree. Water comes from the ground, and carbon atoms enter the tree from the air, right? It comes from the sky. Therefore, almost all trees come from the ground. Sorry, I misspoke, they all come from the air. Of course, a small amount comes from underground minerals, etc.

Of course, I told you oxygen atoms... Oxygen atoms and carbon atoms combine very tightly. So how does the tree cleverly absorb carbon dioxide? At this point, the carbon atoms and oxygen atoms are tightly bound, yet the tree can easily break them down? Ah! Life, is it some mysterious power of life? Wrong, it's the sun's rays. Sunlight shines in and separates the oxygen atoms and carbon atoms. Therefore, sunlight is needed for plants to grow. So the role of the sun is to continuously separate oxygen atoms and carbon atoms. Oxygen, as a kind of bad byproduct, is released into the air, leaving behind carbon atoms and water, which form the substance of the tree. Then we put the substance of the tree in the fireplace. The oxygen produced by the tree wants to combine with the carbon in the tree again. Once you heat it to trigger their combination, the whole process will continue. During their vigorous combination, intense thermal motion will occur. Thus, beautiful light and other things appear. It's as if nothing happened; you've turned oxygen and carbon back into carbon dioxide. But light and heat are produced, which are actually the light and heat of the sun radiating in. So when you light a piece of wood, it's like releasing the sun stored in the wood.

The next question is, why is the sun so active and so hot? I'll stop here and leave you with a question to imagine. Most elastic things, like steel bars or springs, are due to forces related to electricity pulling them back. When you bend something, you're pulling the atoms a little farther apart, so these atoms try to come back together. But a rubber band works differently. There are some long chain-like molecules, and some small molecules that are constantly vibrating and hitting these chain molecules. And the chain molecules are all twisted and funny shapes. When you straighten the rubber band, the chain molecules straighten out. But these chain molecules are constantly being hit from the sides. Other atoms try to twist them, making them contract. Therefore, the rubber band tries to contract. It contracts simply due to heat. So if you heat a rubber band, it will contract more. For example, if you hang a heavy object with a rubber band and then bring a lit match close to the rubber band, it's quite interesting to watch the heavy object rise as the rubber band is heated.

You can also prove this point in another way. To prove that it is indeed heat that drives the contraction of a rubber band. When you stretch a rubber band, it's like compressing the piston and internal gas downwards. If you stretch a rubber band, the stretched chain molecules hit other molecules, making them move faster, so the temperature rises. And when you contract the rubber band, the molecules lose some energy when they hit the chain molecules. It's like hitting something soft; it sinks in and "bang bang." Energy is lost. When you pull the piston out, the atoms hit it and their speed decreases, so the temperature drops. So when a gas expands, its temperature decreases.

The interesting thing is that all the phenomena you observe in this world, such as your gas compressing and heating up, expanding and cooling down, or water evaporating from a cup if it's not covered. All these phenomena can be understood using a simple atomic picture. Thinking this way is very interesting. I don't want to take this kind of thinking too seriously. I think we should imagine happily, without any worries. There won't be a teacher asking questions at the end, otherwise it's an annoying subject.

Different atoms want to be close to each other to varying degrees. For example, oxygen atoms in the air want to be close to carbon atoms. If they get too close, they combine vigorously. If they are not very close, they repel each other and separate. So they don't know they can combine. It's like a ball trying to climb a hill. There's a hole in front of it, into which it can fall, like a crater. A deep opening. The ball just circles around it and doesn't fall in. Because when the ball starts to climb the slope, it rolls back. But if you make it go fast enough to pass the critical point, it will fall into the hole. So if something like wood comes into contact with oxygen, and there are carbon atoms in the wood. The oxygen atoms come and hit the carbon atoms, but the temperature isn't high enough. The oxygen atoms run away again. Air always comes and goes, and nothing happens.

If you heat the oxygen atoms in some way to make them faster, to accelerate a few atoms at first, meaning to get them past the critical point. They get close enough to the carbon atoms, and then they combine vigorously. This will produce more vigorous vibrations, possibly hitting other atoms and making them move faster, so they can pass the critical point and hit other carbon atoms. Their continuous vibration causes other atoms to vibrate together, and a terrible disaster occurs. One atom after another vibrates faster and faster, combining vigorously, and everything changes. This "disaster" is fire. This is one way to describe "fire." This collision is constantly happening, never stopping. Once it starts, it continues to do so. The heat produced gives other atoms the ability to collide and produce more heat, causing more atoms to behave the same way. So this vigorous combination triggers a lot of vibration.

If I place those less energetic atoms over there, for example, if I place a cup of cold coffee next to a pile of burning wood. The atoms in the coffee will vibrate vigorously, that's the heat of the fire. Of course, there will be... See, this is what happens when you start thinking, you can't stop at all. You just want to know how it started. Why did the wood stay with the oxygen for so long without fire appearing before? Where did this heat come from? Actually, it comes from the tree. The substance of the tree is carbon. Where did that carbon come from? It comes from carbon dioxide in the air. People look at trees and think trees grow from the ground. Plants grow from the ground. But if you ask where the substance of the tree comes from, think carefully about where it comes from. Does the tree come from the air? Of course, trees do come from the air. Carbon dioxide in the air enters the tree, changes, kicks out oxygen atoms, forming oxygen and releasing it, leaving carbon atoms. Carbon and water form the substance of the tree. Water comes from the ground, and carbon atoms enter the tree from the air, right? It comes from the sky. Therefore, almost all trees come from the ground. Sorry, I misspoke, they all come from the air. Of course, a small amount comes from underground minerals, etc.

Of course, I told you oxygen atoms... Oxygen atoms and carbon atoms combine very tightly. So how does the tree cleverly absorb carbon dioxide? At this point, the carbon atoms and oxygen atoms are tightly bound, yet the tree can easily break them down? Ah! Life, is it some mysterious power of life? Wrong, it's the sun's rays. Sunlight shines in and separates the oxygen atoms and carbon atoms. Therefore, sunlight is needed for plants to grow. So the role of the sun is to continuously separate oxygen atoms and carbon atoms. Oxygen, as a kind of bad byproduct, is released into the air, leaving behind carbon atoms and water, which form the substance of the tree. Then we put the substance of the tree in the fireplace. The oxygen produced by the tree wants to combine with the carbon in the tree again. Once you heat it to trigger their combination, the whole process will continue. During their vigorous combination, intense thermal motion will occur. Thus, beautiful light and other things appear. It's as if nothing happened; you've turned oxygen and carbon back into carbon dioxide. But light and heat are produced, which are actually the light and heat of the sun radiating in. So when you light a piece of wood, it's like releasing the sun stored in the wood.

The next question is, why is the sun so active and so hot? I'll stop here and leave you with a question to imagine. Most elastic things, like steel bars or springs, are due to forces related to electricity pulling them back. When you bend something, you're pulling the atoms a little farther apart, so these atoms try to come back together. But a rubber band works differently. There are some long chain-like molecules, and some small molecules that are constantly vibrating and hitting these chain molecules. And the chain molecules are all twisted and funny shapes. When you straighten the rubber band, the chain molecules straighten out. But these chain molecules are constantly being hit from the sides. Other atoms try to twist them, making them contract. Therefore, the rubber band tries to contract. It contracts simply due to heat. So if you heat a rubber band, it will contract more. For example, if you hang a heavy object with a rubber band and then bring a lit match close to the rubber band, it's quite interesting to watch the heavy object rise as the rubber band is heated.

You can also prove this point in another way. To prove that it is indeed heat that drives the contraction of a rubber band. When you stretch a rubber band, it's like compressing the piston and internal gas downwards. If you stretch a rubber band, the stretched chain molecules hit other molecules, making them move faster, so the temperature rises. And when you contract the rubber band, the molecules lose some energy when they hit the chain molecules. It's like hitting something soft; it sinks in and "bang bang." Energy is lost. When you pull the piston out, the atoms hit it and their speed decreases, so the temperature drops. So when a gas expands, its temperature decreases.

The interesting thing is that all the phenomena you observe in this world, such as your gas compressing and heating up, expanding and cooling down, or water evaporating from a cup if it's not covered. All these phenomena can be understood using a simple atomic picture. Thinking this way is very interesting. I don't want to take this kind of thinking too seriously. I think we should imagine happily, without any worries. There won't be a teacher asking questions at the end, otherwise it's an annoying subject.

Different atoms want to be close to each other to varying degrees. For example, oxygen atoms in the air want to be close to carbon atoms. If they get too close, they combine vigorously. If they are not very close, they repel each other and separate. So they don't know they can combine. It's like a ball trying to climb a hill. There's a hole in front of it, into which it can fall, like a crater. A deep opening. The ball just circles around it and doesn't fall in. Because when the ball starts to climb the slope, it rolls back. But if you make it go fast enough to pass the critical point, it will fall into the hole. So if something like wood comes into contact with oxygen, and there are carbon atoms in the wood. The oxygen atoms come and hit the carbon atoms, but the temperature isn't high enough. The oxygen atoms run away again. Air always comes and goes, and nothing happens.

If you heat the oxygen atoms in some way to make them faster, to accelerate a few atoms at first, meaning to get them past the critical point. They get close enough to the carbon atoms, and then they combine vigorously. This will produce more vigorous vibrations, possibly hitting other atoms and making them move faster, so they can pass the critical point and hit other carbon atoms. Their continuous vibration causes other atoms to vibrate together, and a terrible disaster occurs. One atom after another vibrates faster and faster, combining vigorously, and everything changes. This "disaster" is fire. This is one way to describe "fire." This collision is constantly happening, never stopping. Once it starts, it continues to do so. The heat produced gives other atoms the ability to collide and produce more heat, causing more atoms to behave the same way. So this vigorous combination triggers a lot of vibration.

If I place those less energetic atoms over there, for example, if I place a cup of cold coffee next to a pile of burning wood. The atoms in the coffee will vibrate vigorously, that's the heat of the fire. Of course, there will be... See, this is what happens when you start thinking, you can't stop at all. You just want to know how it started. Why did the wood stay with the oxygen for so long without fire appearing before? Where did this heat come from? Actually, it comes from the tree. The substance of the tree is carbon. Where did that carbon come from? It comes from carbon dioxide in the air. People look at trees and think trees grow from the ground. Plants grow from the ground. But if you ask where the substance of the tree comes from, think carefully about where it comes from. Does the tree come from the air? Of course, trees do come from the air. Carbon dioxide in the air enters the tree, changes, kicks out oxygen atoms, forming oxygen and releasing it, leaving carbon atoms. Carbon and water form the substance of the tree. Water comes from the ground, and carbon atoms enter the tree from the air, right? It comes from the sky. Therefore, almost all trees come from the ground. Sorry, I misspoke, they all come from the air. Of course, a small amount comes from underground minerals, etc.

Of course, I told you oxygen atoms... Oxygen atoms and carbon atoms combine very tightly. So how does the tree cleverly absorb carbon dioxide? At this point, the carbon atoms and oxygen atoms are tightly bound, yet the tree can easily break them down? Ah! Life, is it some mysterious power of life? Wrong, it's the sun's rays. Sunlight shines in and separates the oxygen atoms and carbon atoms. Therefore, sunlight is needed for plants to grow. So the role of the sun is to continuously separate oxygen atoms and carbon atoms. Oxygen, as a kind of bad byproduct, is released into the air, leaving behind carbon atoms and water, which form the substance of the tree. Then we put the substance of the tree in the fireplace. The oxygen produced by the tree wants to combine with the carbon in the tree again. Once you heat it to trigger their combination, the whole process will continue. During their vigorous combination, intense thermal motion will occur. Thus, beautiful light and other things appear. It's as if nothing happened; you've turned oxygen and carbon back into carbon dioxide. But light and heat are produced, which are actually the light and heat of the sun radiating in. So when you light a piece of wood, it's like releasing the sun stored in the wood.

The next question is, why is the sun so active and so hot? I'll stop here and leave you with a question to imagine. Most elastic things, like steel bars or springs, are due to forces related to electricity pulling them back. When you bend something, you're pulling the atoms a little farther apart, so these atoms try to come back together. But a rubber band works differently. There are some long chain-like molecules, and some small molecules that are constantly vibrating and hitting these chain molecules. And the chain molecules are all twisted and funny shapes. When you straighten the rubber band, the chain molecules straighten out. But these chain molecules are constantly being hit from the sides. Other atoms try to twist them, making them contract. Therefore, the rubber band tries to contract. It contracts simply due to heat. So if you heat a rubber band, it will contract more. For example, if you hang a heavy object with a rubber band and then bring a lit match close to the rubber band, it's quite interesting to watch the heavy object rise as the rubber band is heated.

You can also prove this point in another way. To prove that it is indeed heat that drives the contraction of a rubber band. When you stretch a rubber band, it's like compressing the piston and internal gas downwards. If you stretch a rubber band, the stretched chain molecules hit other molecules, making them move faster, so the temperature rises. And when you contract the rubber band, the molecules lose some energy when they hit the chain molecules. It's like hitting something soft; it sinks in and "bang bang." Energy is lost. When you pull the piston out, the atoms hit it and their speed decreases, so the temperature drops. So when a gas expands, its temperature decreases.

The interesting thing is that all the phenomena you observe in this world, such as your gas compressing and heating up, expanding and cooling down, or water evaporating from a cup if it's not covered. All these phenomena can be understood using a simple atomic picture. Thinking this way is very interesting. I don't want to take this kind of thinking too seriously. I think we should imagine happily, without any worries. There won't be a teacher asking questions at the end, otherwise it's an annoying subject.

Different atoms want to be close to each other to varying degrees. For example, oxygen atoms in the air want to be close to carbon atoms. If they get too close, they combine vigorously. If they are not very close, they repel each other and separate. So they don't know they can combine. It's like a ball trying to climb a hill. There's a hole in front of it, into which it can fall, like a crater. A deep opening. The ball just circles around it and doesn't fall in. Because when the ball starts to climb the slope, it rolls back. But if you make it go fast enough to pass the critical point, it will fall into the hole. So if something like wood comes into contact with oxygen, and there are carbon atoms in the wood. The oxygen atoms come and hit the carbon atoms, but the temperature isn't high enough. The oxygen atoms run away again. Air always comes and goes, and nothing happens.

If you heat the oxygen atoms in some way to make them faster, to accelerate a few atoms at first, meaning to get them past the critical point. They get close enough to the carbon atoms, and then they combine vigorously. This will produce more vigorous vibrations, possibly hitting other atoms and making them move faster, so they can pass the critical point and hit other carbon atoms. Their continuous vibration causes other atoms to vibrate together, and a terrible disaster occurs. One atom after another vibrates faster and faster, combining vigorously, and everything changes. This "disaster" is fire. This is one way to describe "fire." This collision is constantly happening, never stopping. Once it starts, it continues to do so. The heat produced gives other atoms the ability to collide and produce more heat, causing more atoms to behave the same way. So this vigorous combination triggers a lot of vibration.

If I place those less energetic atoms over there, for example, if I place a cup of cold coffee next to a pile of burning wood. The atoms in the coffee will vibrate vigorously, that's the heat of the fire. Of course, there will be... See, this is what happens when you start thinking, you can't stop at all. You just want to know how it started. Why did the wood stay with the oxygen for so long without fire appearing before? Where did this heat come from? Actually, it comes from the tree. The substance of the tree is carbon. Where did that carbon come from? It comes from carbon dioxide in the air. People look at trees and think trees grow from the ground. Plants grow from the ground. But if you ask where the substance of the tree comes from, think carefully about where it comes from. Does the tree come from the air? Of course, trees do come from the air. Carbon dioxide in the air enters the tree, changes, kicks out oxygen atoms, forming oxygen and releasing it, leaving carbon atoms. Carbon and water form the substance of the tree. Water comes from the ground, and carbon atoms enter the tree from the air, right? It comes from the sky. Therefore, almost all trees come from the ground. Sorry, I misspoke, they all come from the air. Of course, a small amount comes from underground minerals, etc.

Of course, I told you oxygen atoms... Oxygen atoms and carbon atoms combine very tightly. So how does the tree cleverly absorb carbon dioxide? At this point, the carbon atoms and oxygen atoms are tightly bound, yet the tree can easily break them down? Ah! Life, is it some mysterious power of life? Wrong, it's the sun's rays. Sunlight shines in and separates the oxygen atoms and carbon atoms. Therefore, sunlight is needed for plants to grow. So the role of the sun is to continuously separate oxygen atoms and carbon atoms. Oxygen, as a kind of bad byproduct, is released into the air, leaving behind carbon atoms and water, which form the substance of the tree. Then we put the substance of the tree in the fireplace. The oxygen produced by the tree wants to combine with the carbon in the tree again. Once you heat it to trigger their combination, the whole process will continue. During their vigorous combination, intense thermal motion will occur. Thus, beautiful light and other things appear. It's as if nothing happened; you've turned oxygen and carbon back into carbon dioxide. But light and heat are produced, which are actually the light and heat of the sun radiating in. So when you light a piece of wood, it's like releasing the sun stored in the wood.

The next question is, why is the sun so active and so hot? I'll stop here and leave you with a question to imagine. Most elastic things, like steel bars or springs, are due to forces related to electricity pulling them back. When you bend something, you're pulling the atoms a little farther apart, so these atoms try to come back together. But a rubber band works differently. There are some long chain-like molecules, and some small molecules that are constantly vibrating and hitting these chain molecules. And the chain molecules are all twisted and funny shapes. When you straighten the rubber band, the chain molecules straighten out. But these chain molecules are constantly being hit from the sides. Other atoms try to twist them, making them contract. Therefore, the rubber band tries to contract. It contracts simply due to heat. So if you heat a rubber band, it will contract more. For example, if you hang a heavy object with a rubber band and then bring a lit match close to the rubber band, it's quite interesting to watch the heavy object rise as the rubber band is heated.

You can also prove this point in another way. To prove that it is indeed heat that drives the contraction of a rubber band. When you stretch a rubber band, it's like compressing the piston and internal gas downwards. If you stretch a rubber band, the stretched chain molecules hit other molecules, making them move faster, so the temperature rises. And when you contract the rubber band, the molecules lose some energy when they hit the chain molecules. It's like hitting something soft; it sinks in and "bang bang." Energy is lost. When you pull the piston out, the atoms hit it and their speed decreases, so the temperature drops. So when a gas expands, its temperature decreases.

The interesting thing is that all the phenomena you observe in this world, such as your gas compressing and heating up, expanding and cooling down, or water evaporating from a cup if it's not covered. All these phenomena can be understood using a simple atomic picture. Thinking this way is very interesting. I don't want to take this kind of thinking too seriously. I think we should imagine happily, without any worries. There won't be a teacher asking questions at the end, otherwise it's an annoying subject.

Different atoms want to be close to each other to varying degrees. For example, oxygen atoms in the air want to be close to carbon atoms. If they get too close, they combine vigorously. If they are not very close, they repel each other and separate. So they don't know they can combine. It's like a ball trying to climb a hill. There's a hole in front of it, into which it can fall, like a crater. A deep opening. The ball just circles around it and doesn't fall in. Because when the ball starts to climb the slope, it rolls back. But if you make it go fast enough to pass the critical point, it will fall into the hole. So if something like wood comes into contact with oxygen, and there are carbon atoms in the wood. The oxygen atoms come and hit the carbon atoms, but the temperature isn't high enough. The oxygen atoms run away again. Air always comes and goes, and nothing happens.

If you heat the oxygen atoms in some way to make them faster, to accelerate a few atoms at first, meaning to get them past the critical point. They get close enough to the carbon atoms, and then they combine vigorously. This will produce more vigorous vibrations, possibly hitting other atoms and making them move faster, so they can pass the critical point and hit other carbon atoms. Their continuous vibration causes other atoms to vibrate together, and a terrible disaster occurs. One atom after another vibrates faster and faster, combining vigorously, and everything changes. This "disaster" is fire. This is one way to describe "fire." This collision is constantly happening, never stopping. Once it starts, it continues to do so. The heat produced gives other atoms the ability to collide and produce more heat, causing more atoms to behave the same way. So this vigorous combination triggers a lot of vibration.

If I place those less energetic atoms over there, for example, if I place a cup of cold coffee next to a pile of burning wood. The atoms in the coffee will vibrate vigorously, that's the heat of the fire. Of course, there will be... See, this is what happens when you start thinking, you can't stop at all. You just want to know how it started. Why did the wood stay with the oxygen for so long without fire appearing before? Where did this heat come from? Actually, it comes from the tree. The substance of the tree is carbon. Where did that carbon come from? It comes from carbon dioxide in the air. People look at trees and think trees grow from the ground. Plants grow from the ground. But if you ask where the substance of the tree comes from, think carefully about where it comes from. Does the tree come from the air? Of course, trees do come from the air. Carbon dioxide in the air enters the tree, changes, kicks out oxygen atoms, forming oxygen and releasing it, leaving carbon atoms. Carbon and water form the substance of the tree. Water comes from the ground, and carbon atoms enter the tree from the air, right? It comes from the sky. Therefore, almost all trees come from the ground. Sorry, I misspoke, they all come from the air. Of course, a small amount comes from underground minerals, etc.

Of course, I told you oxygen atoms... Oxygen atoms and carbon atoms combine very tightly. So how does the tree cleverly absorb carbon dioxide? At this point, the carbon atoms and oxygen atoms are tightly bound, yet the tree can easily break them down? Ah! Life, is it some mysterious power of life? Wrong, it's the sun's rays. Sunlight shines in and separates the oxygen atoms and carbon atoms. Therefore, sunlight is needed for plants to grow. So the role of the sun is to continuously separate oxygen atoms and carbon atoms. Oxygen, as a kind of bad byproduct, is released into the air, leaving behind carbon atoms and water, which form the substance of the tree. Then we put the substance of the tree in the fireplace. The oxygen produced by the tree wants to combine with the carbon in the tree again. Once you heat it to trigger their combination, the whole process will continue. During their vigorous combination, intense thermal motion will occur. Thus, beautiful light and other things appear. It's as if nothing happened; you've turned oxygen and carbon back into carbon dioxide. But light and heat are produced, which are actually the light and heat of the sun radiating in. So when you light a piece of wood, it's like releasing the sun stored in the wood.

The next question is, why is the sun so active and so hot? I'll stop here and leave you with a question to imagine. Most elastic things, like steel bars or springs, are due to forces related to electricity pulling them back. When you bend something, you're pulling the atoms a little farther apart, so these atoms try to come back together. But a rubber band works differently. There are some long chain-like molecules, and some small molecules that are constantly vibrating and hitting these chain molecules. And the chain molecules are all twisted and funny shapes. When you straighten the rubber band, the chain molecules straighten out. But these chain molecules are constantly being hit from the sides. Other atoms try to twist them, making them contract. Therefore, the rubber band tries to contract. It contracts simply due to heat. So if you heat a rubber band, it will contract more. For example, if you hang a heavy object with a rubber band and then bring a lit match close to the rubber band, it's quite interesting to watch the heavy object rise as the rubber band is heated.

You can also prove this point in another way. To prove that it is indeed heat that drives the contraction of a rubber band. When you stretch a rubber band, it's like compressing the piston and internal gas downwards. If you stretch a rubber band, the stretched chain molecules hit other molecules, making them move faster, so the temperature rises. And when you contract the rubber band, the molecules lose some energy when they hit the chain molecules. It's like hitting something soft; it sinks in and "bang bang." Energy is lost. When you pull the piston out, the atoms hit it and their speed decreases, so the temperature drops. So when a gas expands, its temperature decreases.

The interesting thing is that all the phenomena you observe in this world, such as your gas compressing and heating up, expanding and cooling down, or water evaporating from a cup if it's not covered. All these phenomena can be understood using a simple atomic picture. Thinking this way is very interesting. I don't want to take this kind of thinking too seriously. I think we should imagine happily, without any worries. There won't be a teacher asking questions at the end, otherwise it's an annoying subject.

Different atoms want to be close to each other to varying degrees. For example, oxygen atoms in the air want to be close to carbon atoms. If they get too close, they combine vigorously. If they are not very close, they repel each other and separate. So they don't know they can combine. It's like a ball trying to climb a hill. There's a hole in front of it, into which it can fall, like a crater. A deep opening. The ball just circles around it and doesn't fall in. Because when the ball starts to climb the slope, it rolls back. But if you make it go fast enough to pass the critical point, it will fall into the hole. So if something like wood comes into contact with oxygen, and there are carbon atoms in the wood. The oxygen atoms come and hit the carbon atoms, but the temperature isn't high enough. The oxygen atoms run away again. Air always comes and goes, and nothing happens.

If you heat the oxygen atoms in some way to make them faster, to accelerate a few atoms at first, meaning to get them past the critical point. They get close enough to the carbon atoms, and then they combine vigorously. This will produce more vigorous vibrations, possibly hitting other atoms and making them move faster, so they can pass the critical point and hit other carbon atoms. Their continuous vibration causes other atoms to vibrate together, and a terrible disaster occurs. One atom after another vibrates faster and faster, combining vigorously, and everything changes. This "disaster" is fire. This is one way to describe "fire." This collision is constantly happening, never stopping. Once it starts, it continues to do so. The heat produced gives other atoms the ability to collide and produce more heat, causing more atoms to behave the same way. So this vigorous combination triggers a lot of vibration.

If I place those less energetic atoms over there, for example, if I place a cup of cold coffee next to a pile of burning wood. The atoms in the coffee will vibrate vigorously, that's the heat of the fire. Of course, there will be... See, this is what happens when you start thinking, you can't stop at all. You just want to know how it started. Why did the wood stay with the oxygen for so long without fire appearing before? Where did this heat come from? Actually, it comes from the tree. The substance of the tree is carbon. Where did that carbon come from? It comes from carbon dioxide in the air. People look at trees and think trees grow from the ground. Plants grow from the ground. But if you ask where the substance of the tree comes from, think carefully about where it comes from. Does the tree come from the air? Of course, trees do come from the air. Carbon dioxide in the air enters the tree, changes, kicks out oxygen atoms, forming oxygen and releasing it, leaving carbon atoms. Carbon and water form the substance of the tree. Water comes from the ground, and carbon atoms enter the tree from the air, right? It comes from the sky. Therefore, almost all trees come from the ground. Sorry, I misspoke, they all come from the air. Of course, a small amount comes from underground minerals, etc.

Of course, I told you oxygen atoms... Oxygen atoms and carbon atoms combine very tightly. So how does the tree cleverly absorb carbon dioxide? At this point, the carbon atoms and oxygen atoms are tightly bound, yet the tree can easily break them down? Ah! Life, is it some mysterious power of life? Wrong, it's the sun's rays. Sunlight shines in and separates the oxygen atoms and carbon atoms. Therefore, sunlight is needed for plants to grow. So the role of the sun is to continuously separate oxygen atoms and carbon atoms. Oxygen, as a kind of bad byproduct, is released into the air, leaving behind carbon atoms and water, which form the substance of the tree. Then we put the substance of the tree in the fireplace. The oxygen produced by the tree wants to combine with the carbon in the tree again. Once you heat it to trigger their combination, the whole process will continue. During their vigorous combination, intense thermal motion will occur. Thus, beautiful light and other things appear. It's as if nothing happened; you've turned oxygen and carbon back into carbon dioxide. But light and heat are produced, which are actually the light and heat of the sun radiating in. So when you light a piece of wood, it's like releasing the sun stored in the wood.

The next question is, why is the sun so active and so hot? I'll stop here and leave you with a question to imagine. Most elastic things, like steel bars or springs, are due to forces related to electricity pulling them back. When you bend something, you're pulling the atoms a little farther apart, so these atoms try to come back together. But a rubber band works differently. There are some long chain-like molecules, and some small molecules that are constantly vibrating and hitting these chain molecules. And the chain molecules are all twisted and funny shapes. When you straighten the rubber band, the chain molecules straighten out. But these chain molecules are constantly being hit from the sides. Other atoms try to twist them, making them contract. Therefore, the rubber band tries to contract. It contracts simply due to heat. So if you heat a rubber band, it will contract more. For example, if you hang a heavy object with a rubber band and then bring a lit match close to the rubber band, it's quite interesting to watch the heavy object rise as the rubber band is heated.

You can also prove this point in another way. To prove that it is indeed heat that drives the contraction of a rubber band. When you stretch a rubber band, it's like compressing the piston and internal gas downwards. If you stretch a rubber band, the stretched chain molecules hit other molecules, making them move faster, so the temperature rises. And when you contract the rubber band, the molecules lose some energy when they hit the chain molecules. It's like hitting something soft; it sinks in and "bang bang." Energy is lost. When you pull the piston out, the atoms hit it and their speed decreases, so the temperature drops. So when a gas expands, its temperature decreases.

The interesting thing is that all the phenomena you observe in this world, such as your gas compressing and heating up, expanding and cooling down, or water evaporating from a cup if it's not covered. All these phenomena can be understood using a simple atomic picture. Thinking this way is very interesting. I don't want to take this kind of thinking too seriously. I think we should imagine happily, without any worries. There won't be a teacher asking questions at the end, otherwise it's an annoying subject.

Different atoms want to be close to each other to varying degrees. For example, oxygen atoms in the air want to be close to carbon atoms. If they get too close, they combine vigorously. If they are not very close, they repel each other and separate. So they don't know they can combine. It's like a ball trying to climb a hill. There's a hole in front of it, into which it can fall, like a crater. A deep opening. The ball just circles around it and doesn't fall in. Because when the ball starts to climb the slope, it rolls back. But if you make it go fast enough to pass the critical point, it will fall into the hole. So if something like wood comes into contact with oxygen, and there are carbon atoms in the wood. The oxygen atoms come and hit the carbon atoms, but the temperature isn't high enough. The oxygen atoms run away again. Air always comes and goes, and nothing happens.

If you heat the oxygen atoms in some way to make them faster, to accelerate a few atoms at first, meaning to get them past the critical point. They get close enough to the carbon atoms, and then they combine vigorously. This will produce more vigorous vibrations, possibly hitting other atoms and making them move faster, so they can pass the critical point and hit other carbon atoms. Their continuous vibration causes other atoms to vibrate together, and a terrible disaster occurs. One atom after another vibrates faster and faster, combining vigorously, and everything changes. This "disaster" is fire. This is one way to describe "fire." This collision is constantly happening, never stopping. Once it starts, it continues to do so. The heat produced gives other atoms the ability to collide and produce more heat, causing more atoms to behave the same way. So this vigorous combination triggers a lot of vibration.

If I place those less energetic atoms over there, for example, if I place a cup of cold coffee next to a pile of burning wood. The atoms in the coffee will vibrate vigorously, that's the heat of the fire. Of course, there will be... See, this is what happens when you start thinking, you can't stop at all. You just want to know how it started. Why did the wood stay with the oxygen for so long without fire appearing before? Where did this heat come from? Actually, it comes from the tree. The substance of the tree is carbon. Where did that carbon come from? It comes from carbon dioxide in the air. People look at trees and think trees grow from the ground. Plants grow from the ground. But if you ask where the substance of the tree comes from, think carefully about where it comes from. Does the tree come from the air? Of course, trees do come from the air. Carbon dioxide in the air enters the tree, changes, kicks out oxygen atoms, forming oxygen and releasing it, leaving carbon atoms. Carbon and water form the substance of the tree. Water comes from the ground, and carbon atoms enter the tree from the air, right? It comes from the sky. Therefore, almost all trees come from the ground. Sorry, I misspoke, they all come from the air. Of course, a small amount comes from underground minerals, etc.

Of course, I told you oxygen atoms... Oxygen atoms and carbon atoms combine very tightly. So how does the tree cleverly absorb carbon dioxide? At this point, the carbon atoms and oxygen atoms are tightly bound, yet the tree can easily break them down? Ah! Life, is it some mysterious power of life? Wrong, it's the sun's rays. Sunlight shines in and separates the oxygen atoms and carbon atoms. Therefore, sunlight is needed for plants to grow. So the role of the sun is to continuously separate oxygen atoms and carbon atoms. Oxygen, as a kind of bad byproduct, is released into the air, leaving behind carbon atoms and water, which form the substance of the tree. Then we put the substance of the tree in the fireplace. The oxygen produced by the tree wants to combine with the carbon in the tree again. Once you heat it to trigger their combination, the whole process will continue. During their vigorous combination, intense thermal motion will occur. Thus, beautiful light and other things appear. It's as if nothing happened; you've turned oxygen and carbon back into carbon dioxide. But light and heat are produced, which are actually the light and heat of the sun radiating in. So when you light a piece of wood, it's like releasing the sun stored in the wood.

The next question is, why is the sun so active and so hot? I'll stop here and leave you with a question to imagine. Most elastic things, like steel bars or springs, are due to forces related to electricity pulling them back. When you bend something, you're pulling the atoms a little farther apart, so these atoms try to come back together. But a rubber band works differently. There are some long chain-like molecules, and some small molecules that are constantly vibrating and hitting these chain molecules. And the chain molecules are all twisted and funny shapes. When you straighten the rubber band, the chain molecules straighten out. But these chain molecules are constantly being hit from the sides. Other atoms try to twist them, making them contract. Therefore, the rubber band tries to contract. It contracts simply due to heat. So if you heat a rubber band, it will contract more. For example, if you hang a heavy object with a rubber band and then bring a lit match close to the rubber band, it's quite interesting to watch the heavy object rise as the rubber band is heated.

You can also prove this point in another way. To prove that it is indeed heat that drives the contraction of a rubber band. When you stretch a rubber band, it's like compressing the piston and internal gas downwards. If you stretch a rubber band, the stretched chain molecules hit other molecules, making them move faster, so the temperature rises. And when you contract the rubber band, the molecules lose some energy when they hit the chain molecules. It's like hitting something soft; it sinks in and "bang bang." Energy is lost. When you pull the piston out, the atoms hit it and their speed decreases, so the temperature drops. So when a gas expands, its temperature decreases.

The interesting thing is that all the phenomena you observe in this world, such as your gas compressing and heating up, expanding and cooling down, or water evaporating from a cup if it's not covered. All these phenomena can be understood using a simple atomic picture. Thinking this way is very interesting. I don't want to take this kind of thinking too seriously. I think we should imagine happily, without any worries. There won't be a teacher asking questions at the end, otherwise it's an annoying subject.

Different atoms want to be close to each other to varying degrees. For example, oxygen atoms in the air want to be close to carbon atoms. If they get too close, they combine vigorously. If they are not very close, they repel each other and separate. So they don't know they can combine. It's like a ball trying to climb a hill. There's a hole in front of it, into which it can fall, like a crater. A deep opening. The ball just circles around it and doesn't fall in. Because when the ball starts to climb the slope, it rolls back. But if you make it go fast enough to pass the critical point, it will fall into the hole. So if something like wood comes into contact with oxygen, and there are carbon atoms in the wood. The oxygen atoms come and hit the carbon atoms, but the temperature isn't high enough. The oxygen atoms run away again. Air always comes and goes, and nothing happens.

If you heat the oxygen atoms in some way to make them faster, to accelerate a few atoms at first, meaning to get them past the critical point. They get close enough to the carbon atoms, and then they combine vigorously. This will produce more vigorous vibrations, possibly hitting other atoms and making them move faster, so they can pass the critical point and hit other carbon atoms. Their continuous vibration causes other atoms to vibrate together, and a terrible disaster occurs. One atom after another vibrates faster and faster, combining vigorously, and everything changes. This "disaster" is fire. This is one way to describe "fire." This collision is constantly happening, never stopping. Once it starts, it continues to do so. The heat produced gives other atoms the ability to collide and produce more heat, causing more atoms to behave the same way. So this vigorous combination triggers a lot of vibration.

If I place those less energetic atoms over there, for example, if I place a cup of cold coffee next to a pile of burning wood. The atoms in the coffee will vibrate vigorously, that's the heat of the fire. Of course, there will be... See, this is what happens when you start thinking, you can't stop at all. You just want to know how it started. Why did the wood stay with the oxygen for so long without fire appearing before? Where did this heat come from? Actually, it comes from the tree. The substance of the tree is carbon. Where did that carbon come from? It comes from carbon dioxide in the air. People look at trees and think trees grow from the ground. Plants grow from the ground. But if you ask where the substance of the tree comes from, think carefully about where it comes from. Does the tree come from the air? Of course, trees do come from the air. Carbon dioxide in the air enters the tree, changes, kicks out oxygen atoms, forming oxygen and releasing it, leaving carbon atoms. Carbon and water form the substance of the tree. Water comes from the ground, and carbon atoms enter the tree from the air, right? It comes from the sky. Therefore, almost all trees come from the ground. Sorry, I misspoke, they all come from the air. Of course, a small amount comes from underground minerals, etc.

Of course, I told you oxygen atoms... Oxygen atoms and carbon atoms combine very tightly. So how does the tree cleverly absorb carbon dioxide? At this point, the carbon atoms and oxygen atoms are tightly bound, yet the tree can easily break them down? Ah! Life, is it some mysterious power of life? Wrong, it's the sun's rays. Sunlight shines in and separates the oxygen atoms and carbon atoms. Therefore, sunlight is needed for plants to grow. So the role of the sun is to continuously separate oxygen atoms and carbon atoms. Oxygen, as a kind of bad byproduct, is released into the air, leaving behind carbon atoms and water, which form the substance of the tree. Then we put the substance of the tree in the fireplace. The oxygen produced by the tree wants to combine with the carbon in the tree again. Once you heat it to trigger their combination, the whole process will continue. During their vigorous combination, intense thermal motion will occur. Thus, beautiful light and other things appear. It's as if nothing happened; you've turned oxygen and carbon back into carbon dioxide. But light and heat are produced, which are actually the light and heat of the sun radiating in. So when you light a piece of wood, it's like releasing the sun stored in the wood.

The next question is, why is the sun so active and so hot? I'll stop here and leave you with a question to imagine. Most elastic things, like steel bars or springs, are due to forces related to electricity pulling them back. When you bend something, you're pulling the atoms a little farther apart, so these atoms try to come back together. But a rubber band works differently. There are some long chain-like molecules, and some small molecules that are constantly vibrating and hitting these chain molecules. And the chain molecules are all twisted and funny shapes. When you straighten the rubber band, the chain molecules straighten out. But these chain molecules are constantly being hit from the sides. Other atoms try to twist them, making them contract. Therefore, the rubber band tries to contract. It contracts simply due to heat. So if you heat a rubber band, it will contract more. For example, if you hang a heavy object with a rubber band and then bring a lit match close to the rubber band, it's quite interesting to watch the heavy object rise as the rubber band is heated.

You can also prove this point in another way. To prove that it is indeed heat that drives the contraction of a rubber band. When you stretch a rubber band, it's like compressing the piston and internal gas downwards. If you stretch a rubber band, the stretched chain molecules hit other molecules, making them move faster, so the temperature rises. And when you contract the rubber band, the molecules lose some energy when they hit the chain molecules. It's like hitting something soft; it sinks in and "bang bang." Energy is lost. When you pull the piston out, the atoms hit it and their speed decreases, so the temperature drops. So when a gas expands, its temperature decreases.

The interesting thing is that all the phenomena you observe in this world, such as your gas compressing and heating up, expanding and cooling down, or water evaporating from a cup if it's not covered. All these phenomena can be understood using a simple atomic picture. Thinking this way is very interesting. I don't want to take this kind of thinking too seriously. I think we should imagine happily, without any worries. There won't be a teacher asking questions at the end, otherwise it's an annoying subject.

Different atoms want to be close to each other to varying degrees. For example, oxygen atoms in the air want to be close to carbon atoms. If they get too close, they combine vigorously. If they are not very close, they repel each other and separate. So they don't know they can combine. It's like a ball trying to climb a hill. There's a hole in front of it, into which it can fall, like a crater. A deep opening. The ball just circles around it and doesn't fall in. Because when the ball starts to climb the slope, it rolls back. But if you make it go fast enough to pass the critical point, it will fall into the hole. So if something like wood comes into contact with oxygen, and there are carbon atoms in the wood. The oxygen atoms come and hit the carbon atoms, but the temperature isn't high enough. The oxygen atoms run away again. Air always comes and goes, and nothing happens.

If you heat the oxygen atoms in some way to make them faster, to accelerate a few atoms at first, meaning to get them past the critical point. They get close enough to the carbon atoms, and then they combine vigorously. This will produce more vigorous vibrations, possibly hitting other atoms and making them move faster, so they can pass the critical point and hit other carbon atoms. Their continuous vibration causes other atoms to vibrate together, and a terrible disaster occurs. One atom after another vibrates faster and faster, combining vigorously, and everything changes. This "disaster" is fire. This is one way to describe "fire." This collision is constantly happening, never stopping. Once it starts, it continues to do so. The heat produced gives other atoms the ability to collide and produce more heat, causing more atoms to behave the same way. So this vigorous combination triggers a lot of vibration.

If I place those less energetic atoms over there, for example, if I place a cup of cold coffee next to a pile of burning wood. The atoms in the coffee will vibrate vigorously, that's the heat of the fire. Of course, there will be... See, this is what happens when you start thinking, you can't stop at all. You just want to know how it started. Why did the wood stay with the oxygen for so long without fire appearing before? Where did this heat come from? Actually, it comes from the tree. The substance of the tree is carbon. Where did that carbon come from? It comes from carbon dioxide in the air. People look at trees and think trees grow from the ground. Plants grow from the ground. But if you ask where the substance of the tree comes from, think carefully about where it comes from. Does the tree come from the air? Of course, trees do come from the air. Carbon dioxide in the air enters the tree, changes, kicks out oxygen atoms, forming oxygen and releasing it, leaving carbon atoms. Carbon and water form the substance of the tree. Water comes from the ground, and carbon atoms enter the tree from the air, right? It comes from the sky. Therefore, almost all trees come from the ground. Sorry, I misspoke, they all come from the air. Of course, a small amount comes from underground minerals, etc.

Of course, I told you oxygen atoms... Oxygen atoms and carbon atoms combine very tightly. So how does the tree cleverly absorb carbon dioxide? At this point, the carbon atoms and oxygen atoms are tightly bound, yet the tree can easily break them down? Ah! Life, is it some mysterious power of life? Wrong, it's the sun's rays. Sunlight shines in and separates the oxygen atoms and carbon atoms. Therefore, sunlight is needed for plants to grow. So the role of the sun is to continuously separate oxygen atoms and carbon atoms. Oxygen, as a kind of bad byproduct, is released into the air, leaving behind carbon atoms and water, which form the substance of the tree. Then we put the substance of the tree in the fireplace. The oxygen produced by the tree wants to combine with the carbon in the tree again. Once you heat it to trigger their combination, the whole process will continue. During their vigorous combination, intense thermal motion will occur. Thus, beautiful light and other things appear. It's as if nothing happened; you've turned oxygen and carbon back into carbon dioxide. But light and heat are produced, which are actually the light and heat of the sun radiating in. So when you light a piece of wood, it's like releasing the sun stored in the wood.

The next question is, why is the sun so active and so hot? I'll stop here and leave you with a question to imagine. Most elastic things, like steel bars or springs, are due to forces related to electricity pulling them back. When you bend something, you're pulling the atoms a little farther apart, so these atoms try to come back together. But a rubber band works differently. There are some long chain-like molecules, and some small molecules that are constantly vibrating and hitting these chain molecules. And the chain molecules are all twisted and funny shapes. When you straighten the rubber band, the chain molecules straighten out. But these chain molecules are constantly being hit from the sides. Other atoms try to twist them, making them contract. Therefore, the rubber band tries to contract. It contracts simply due to heat. So if you heat a rubber band, it will contract more. For example, if you hang a heavy object with a rubber band and then bring a lit match close to the rubber band, it's quite interesting to watch the heavy object rise as the rubber band is heated.

You can also prove this point in another way. To prove that it is indeed heat that drives the contraction of a rubber band. When you stretch a rubber band, it's like compressing the piston and internal gas downwards. If you stretch a rubber band, the stretched chain molecules hit other molecules, making them move faster, so the temperature rises. And when you contract the rubber band, the molecules lose some energy when they hit the chain molecules. It's like hitting something soft; it sinks in and "bang bang." Energy is lost. When you pull the piston out, the atoms hit it and their speed decreases, so the temperature drops. So when a gas expands, its temperature decreases.

The interesting thing is that all the phenomena you observe in this world, such as your gas compressing and heating up, expanding and cooling down, or water evaporating from a cup if it's not covered. All these phenomena can be understood using a simple atomic picture. Thinking this way is very interesting. I don't want to take this kind of thinking too seriously. I think we should imagine happily, without any worries. There won't be a teacher asking questions at the end, otherwise it's an annoying subject.

Different atoms want to be close to each other to varying degrees. For example, oxygen atoms in the air want to be close to carbon atoms. If they get too close, they combine vigorously. If they are not very close, they repel each other and separate. So they don't know they can combine. It's like a ball trying to climb a hill. There's a hole in front of it, into which it can fall, like a crater. A deep opening. The ball just circles around it and doesn't fall in. Because when the ball starts to climb the slope, it rolls back. But if you make it go fast enough to pass the critical point, it will fall into the hole. So if something like wood comes into contact with oxygen, and there are carbon atoms in the wood. The oxygen atoms come and hit the carbon atoms, but the temperature isn't high enough. The oxygen atoms run away again. Air always comes and goes, and nothing happens.

If you heat the oxygen atoms in some way to make them faster, to accelerate a few atoms at first, meaning to get them past the critical point. They get close enough to the carbon atoms, and then they combine vigorously. This will produce more vigorous vibrations, possibly hitting other atoms and making them move faster, so they can pass the critical point and hit other carbon atoms. Their continuous vibration causes other atoms to vibrate together, and a terrible disaster occurs. One atom after another vibrates faster and faster, combining vigorously, and everything changes. This "disaster" is fire. This is one way to describe "fire." This collision is constantly happening, never stopping. Once it starts, it continues to do so. The heat produced gives other atoms the ability to collide and produce more heat, causing more atoms to behave the same way. So this vigorous combination triggers a lot of vibration.

If I place those less energetic atoms over there, for example, if I place a cup of cold coffee next to a pile of burning wood. The atoms in the coffee will vibrate vigorously, that's the heat of the fire. Of course, there will be... See, this is what happens when you start thinking, you can't stop at all. You just want to know how it started. Why did the wood stay with the oxygen for so long without fire appearing before? Where did this heat come from? Actually, it comes from the tree. The substance of the tree is carbon. Where did that carbon come from? It comes from carbon dioxide in the air. People look at trees and think trees grow from the ground. Plants grow from the ground. But if you ask where the substance of the tree comes from, think carefully about where it comes from. Does the tree come from the air? Of course, trees do come from the air. Carbon dioxide in the air enters the tree, changes, kicks out oxygen atoms, forming oxygen and releasing it, leaving carbon atoms. Carbon and water form the substance of the tree. Water comes from the ground, and carbon atoms enter the tree from the air, right? It comes from the sky. Therefore, almost all trees come from the ground. Sorry, I misspoke, they all come from the air. Of course, a small amount comes from underground minerals, etc.

Of course, I told you oxygen atoms... Oxygen atoms and carbon atoms combine very tightly. So how does the tree cleverly absorb carbon dioxide? At this point, the carbon atoms and oxygen atoms are tightly bound, yet the tree can easily break them down? Ah! Life, is it some mysterious power of life? Wrong, it's the sun's rays. Sunlight shines in and separates the oxygen atoms and carbon atoms. Therefore, sunlight is needed for plants to grow. So the role of the sun is to continuously separate oxygen atoms and carbon atoms. Oxygen, as a kind of bad byproduct, is released into the air, leaving behind carbon atoms and water, which form the substance of the tree. Then we put the substance of the tree in the fireplace. The oxygen produced by the tree wants to combine with the carbon in the tree again. Once you heat it to trigger their combination, the whole process will continue. During their vigorous combination, intense thermal motion will occur. Thus, beautiful light and other things appear. It's as if nothing happened; you've turned oxygen and carbon back into carbon dioxide. But light and heat are produced, which are actually the light and heat of the sun radiating in. So when you light a piece of wood, it's like releasing the sun stored in the wood.

The next question is, why is the sun so active and so hot? I'll stop here and leave you with a question to imagine. Most elastic things, like steel bars or springs, are due to forces related to electricity pulling them back. When you bend something, you're pulling the atoms a little farther apart, so these atoms try to come back together. But a rubber band works differently. There are some long chain-like molecules, and some small molecules that are constantly vibrating and hitting these chain molecules. And the chain molecules are all twisted and funny shapes. When you straighten the rubber band, the chain molecules straighten out. But these chain molecules are constantly being hit from the sides. Other atoms try to twist them, making them contract. Therefore, the rubber band tries to contract. It contracts simply due to heat. So if you heat a rubber band, it will contract more. For example, if you hang a heavy object with a rubber band and then bring a lit match close to the rubber band, it's quite interesting to watch the heavy object rise as the rubber band is heated.

You can also prove this point in another way. To prove that it is indeed heat that drives the contraction of a rubber band. When you stretch a rubber band, it's like compressing the piston and internal gas downwards. If you stretch a rubber band, the stretched chain molecules hit other molecules, making them move faster, so the temperature rises. And when you contract the rubber band, the molecules lose some energy when they hit the chain molecules. It's like hitting something soft; it sinks in and "bang bang." Energy is lost. When you pull the piston out, the atoms hit it and their speed decreases, so the temperature drops. So when a gas expands, its temperature decreases.

The interesting thing is that all the phenomena you observe in this world, such as your gas compressing and heating up, expanding and cooling down, or water evaporating from a cup if it's not covered. All these phenomena can be understood using a simple atomic picture. Thinking this way is very interesting. I don't want to take this kind of thinking too seriously. I think we should imagine happily, without any worries. There won't be a teacher asking questions at the end, otherwise it's an annoying subject.

Different atoms want to be close to each other to varying degrees. For example, oxygen atoms in the air want to be close to carbon atoms. If they get too close, they combine vigorously. If they are not very close, they repel each other and separate. So they don't know they can combine. It's like a ball trying to climb a hill. There's a hole in front of it, into which it can fall, like a crater. A deep opening. The ball just circles around it and doesn't fall in. Because when the ball starts to climb the slope, it rolls back. But if you make it go fast enough to pass the critical point, it will fall into the hole. So if something like wood comes into contact with oxygen, and there are carbon atoms in the wood. The oxygen atoms come and hit the carbon atoms, but the temperature isn't high enough. The oxygen atoms run away again. Air always comes and goes, and nothing happens.

If you heat the oxygen atoms in some way to make them faster, to accelerate a few atoms at first, meaning to get them past the critical point. They get close enough to the carbon atoms, and then they combine vigorously. This will produce more vigorous vibrations, possibly hitting other atoms and making them move faster, so they can pass the critical point and hit other carbon atoms. Their continuous vibration causes other atoms to vibrate together, and a terrible disaster occurs. One atom after another vibrates faster and faster, combining vigorously, and everything changes. This "disaster" is fire. This is one way to describe "fire." This collision is constantly happening, never stopping. Once it starts, it continues to do so. The heat produced gives other atoms the ability to collide and produce more heat, causing more atoms to behave the same way. So this vigorous combination triggers a lot of vibration.

If I place those less energetic atoms over there, for example, if I place a cup of cold coffee next to a pile of burning wood. The atoms in the coffee will vibrate vigorously, that's the heat of the fire. Of course, there will be... See, this is what happens when you start thinking, you can't stop at all. You just want to know how it started. Why did the wood stay with the oxygen for so long without fire appearing before? Where did this heat come from? Actually, it comes from the tree. The substance of the tree is carbon. Where did that carbon come from? It comes from carbon dioxide in the air. People look at trees and think trees grow from the ground. Plants grow from the ground. But if you ask where the substance of the tree comes from, think carefully about where it comes from. Does the tree come from the air? Of course, trees do come from the air. Carbon dioxide in the air enters the tree, changes, kicks out oxygen atoms, forming oxygen and releasing it, leaving carbon atoms. Carbon and water form the substance of the tree. Water comes from the ground, and carbon atoms enter the tree from the air, right? It comes from the sky. Therefore, almost all trees come from the ground. Sorry, I misspoke, they all come from the air. Of course, a small amount comes from underground minerals, etc.

Of course, I told you oxygen atoms... Oxygen atoms and carbon atoms combine very tightly. So how does the tree cleverly absorb carbon dioxide? At this point, the carbon atoms and oxygen atoms are tightly bound, yet the tree can easily break them down? Ah! Life, is it some mysterious power of life? Wrong, it's the sun's rays. Sunlight shines in and separates the oxygen atoms and carbon atoms. Therefore, sunlight is needed for plants to grow. So the role of the sun is to continuously separate oxygen atoms and carbon atoms. Oxygen, as a kind of bad byproduct, is released into the air, leaving behind carbon atoms and water, which form the substance of the tree. Then we put the substance of the tree in the fireplace. The oxygen produced by the tree wants to combine with the carbon in the tree again. Once you heat it to trigger their combination, the whole process will continue. During their vigorous combination, intense thermal motion will occur. Thus, beautiful light and other things appear. It's as if nothing happened; you've turned oxygen and carbon back into carbon dioxide. But light and heat are produced, which are actually the light and heat of the sun radiating in. So when you light a piece of wood, it's like releasing the sun stored in the wood.

The next question is, why is the sun so active and so hot? I'll stop here and leave you with a question to imagine. Most elastic things, like steel bars or springs, are due to forces related to electricity pulling them back. When you bend something, you're pulling the atoms a little farther apart, so these atoms try to come back together. But a rubber band works differently. There are some long chain-like molecules, and some small molecules that are constantly vibrating and hitting these chain molecules. And the chain molecules are all twisted and funny shapes. When you straighten the rubber band, the chain molecules straighten out. But these chain molecules are constantly being hit from the sides. Other atoms try to twist them, making them contract. Therefore, the rubber band tries to contract. It contracts simply due to heat. So if you heat a rubber band, it will contract more. For example, if you hang a heavy object with a rubber band and then bring a lit match close to the rubber band, it's quite interesting to watch the heavy object rise as the rubber band is heated.

You can also prove this point in another way. To prove that it is indeed heat that drives the contraction of a rubber band. When you stretch a rubber band, it's like compressing the piston and internal gas downwards. If you stretch a rubber band, the stretched chain molecules hit other molecules, making them move faster, so the temperature rises. And when you contract the rubber band, the molecules lose some energy when they hit the chain molecules. It's like hitting something soft; it sinks in and "bang bang." Energy is lost. When you pull the piston out, the atoms hit it and their speed decreases, so the temperature drops. So when a gas expands, its temperature decreases.

The interesting thing is that all the phenomena you observe in this world, such as your gas compressing and heating up, expanding and cooling down, or water evaporating from a cup if it's not covered. All these phenomena can be understood using a simple atomic picture. Thinking this way is very interesting. I don't want to take this kind of thinking too seriously. I think we should imagine happily, without any worries. There won't be a teacher asking questions at the end, otherwise it's an annoying subject.

Different atoms want to be close to each other to varying degrees. For example, oxygen atoms in the air want to be close to carbon atoms. If they get too close, they combine vigorously. If they are not very close, they repel each other and separate. So they don't know they can combine. It's like a ball trying to climb a hill. There's a hole in front of it, into which it can fall, like a crater. A deep opening. The ball just circles around it and doesn't fall in. Because when the ball starts to climb the slope, it rolls back. But if you make it go fast enough to pass the critical point, it will fall into the hole. So if something like wood comes into contact with oxygen, and there are carbon atoms in the wood. The oxygen atoms come and hit the carbon atoms, but the temperature isn't high enough. The oxygen atoms run away again. Air always comes and goes, and nothing happens.

If you heat the oxygen atoms in some way to make them faster, to accelerate a few atoms at first, meaning to get them past the critical point. They get close enough to the carbon atoms, and then they combine vigorously. This will produce more vigorous vibrations, possibly hitting other atoms and making them move faster, so they can pass the critical point and hit other carbon atoms. Their continuous vibration causes other atoms to vibrate together, and a terrible disaster occurs. One atom after another vibrates faster and faster, combining vigorously, and everything changes. This "disaster" is fire. This is one way to describe "fire." This collision is constantly happening, never stopping. Once it starts, it continues to do so. The heat produced gives other atoms the ability to collide and produce more heat, causing more atoms to behave the same way. So this vigorous combination triggers a lot of vibration.

If I place those less energetic atoms over there, for example, if I place a cup of cold coffee next to a pile of burning wood. The atoms in the coffee will vibrate vigorously, that's the heat of the fire. Of course, there will be... See, this is what happens when you start thinking, you can't stop at all. You just want to know how it started. Why did the wood stay with the oxygen for so long without fire appearing before? Where did this heat come from? Actually, it comes from the tree. The substance of the tree is carbon. Where did that carbon come from? It comes from carbon dioxide in the air. People look at trees and think trees grow from the ground. Plants grow from the ground. But if you ask where the substance of the tree comes from, think carefully about where it comes from. Does the tree come from the air? Of course, trees do come from the air. Carbon dioxide in the air enters the tree, changes, kicks out oxygen atoms, forming oxygen and releasing it, leaving carbon atoms. Carbon and water form the substance of the tree. Water comes from the ground, and carbon atoms enter the tree from the air, right? It comes from the sky. Therefore, almost all trees come from the ground. Sorry, I misspoke, they all come from the air. Of course, a small amount comes from underground minerals, etc.

Of course, I told you oxygen atoms... Oxygen atoms and carbon atoms combine very tightly. So how does the tree cleverly absorb carbon dioxide? At this point, the carbon atoms and oxygen atoms are tightly bound, yet the tree can easily break them down? Ah! Life, is it some mysterious power of life? Wrong, it's the sun's rays. Sunlight shines in and separates the oxygen atoms and carbon atoms. Therefore, sunlight is needed for plants to grow. So the role of the sun is to continuously separate oxygen atoms and carbon atoms. Oxygen, as a kind of bad byproduct, is released into the air, leaving behind carbon atoms and water, which form the substance of the tree. Then we put the substance of the tree in the fireplace. The oxygen produced by the tree wants to combine with the carbon in the tree again. Once you heat it to trigger their combination, the whole process will continue. During their vigorous combination, intense thermal motion will occur. Thus, beautiful light and other things appear. It's as if nothing happened; you've turned oxygen and carbon back into carbon dioxide. But light and heat are produced, which are actually the light and heat of the sun radiating in. So when you light a piece of wood, it's like releasing the sun stored in the wood.

The next question is, why is the sun so active and so hot? I'll stop here and leave you with a question to imagine. Most elastic things, like steel bars or springs, are due to forces related to electricity pulling them back. When you bend something, you're pulling the atoms a little farther apart, so these atoms try to come back together. But a rubber band works differently. There are some long chain-like molecules, and some small molecules that are constantly vibrating and hitting these chain molecules. And the chain molecules are all twisted and funny shapes. When you straighten the rubber band, the chain molecules straighten out. But these chain molecules are constantly being hit from the sides. Other atoms try to twist them, making them contract. Therefore, the rubber band tries to contract. It contracts simply due to heat. So if you heat a rubber band, it will contract more. For example, if you hang a heavy object with a rubber band and then bring a lit match close to the rubber band, it's quite interesting to watch the heavy object rise as the rubber band is heated.

You can also prove this point in another way. To prove that it is indeed heat that drives the contraction of a rubber band. When you stretch a rubber band, it's like compressing the piston and internal gas downwards. If you stretch a rubber band, the stretched chain molecules hit other molecules, making them move faster, so the temperature rises. And when you contract the rubber band, the molecules lose some energy when they hit the chain molecules. It's like hitting something soft; it sinks in and "bang bang." Energy is lost. When you pull the piston out, the atoms hit it and their speed decreases, so the temperature drops. So when a gas expands, its temperature decreases.

The interesting thing is that all the phenomena you observe in this world, such as your gas compressing and heating up, expanding and cooling down, or water evaporating from a cup if it's not covered. All these phenomena can be understood using a simple atomic picture. Thinking this way is very interesting. I don't want to take this kind of thinking too seriously. I think we should imagine happily, without any worries. There won't be a teacher asking questions at the end, otherwise it's an annoying subject.

Different atoms want to be close to each other to varying degrees. For example, oxygen atoms in the air want to be close to carbon atoms. If they get too close, they combine vigorously. If they are not very close, they repel each other and separate. So they don't know they can combine. It's like a ball trying to climb a hill. There's a hole in front of it, into which it can fall, like a crater. A deep opening. The ball just circles around it and doesn't fall in. Because when the ball starts to climb the slope, it rolls back. But if you make it go fast enough to pass the critical point, it will fall into the hole. So if something like wood comes into contact with oxygen, and there are carbon atoms in the wood. The oxygen atoms come and hit the carbon atoms, but the temperature isn't high enough. The oxygen atoms run away again. Air always comes and goes, and nothing happens.

If you heat the oxygen atoms in some way to make them faster, to accelerate a few atoms at first, meaning to get them past the critical point. They get close enough to the carbon atoms, and then they combine vigorously. This will produce more vigorous vibrations, possibly hitting other atoms and making them move faster, so they can pass the critical point and hit other carbon atoms. Their continuous vibration causes other atoms to vibrate together, and a terrible disaster occurs. One atom after another vibrates faster and faster, combining vigorously, and everything changes. This "disaster" is fire. This is one way to describe "fire." This collision is constantly happening, never stopping. Once it starts, it continues to do so. The heat produced gives other atoms the ability to collide and produce more heat, causing more atoms to behave the same way. So this vigorous combination triggers a lot of vibration.

If I place those less energetic atoms over there, for example, if I place a cup of cold coffee next to a pile of burning wood. The atoms in the coffee will vibrate vigorously, that's the heat of the fire. Of course, there will be... See, this is what happens when you start thinking, you can't stop at all. You just want to know how it started. Why did the wood stay with the oxygen for so long without fire appearing before? Where did this heat come from? Actually, it comes from the tree. The substance of the tree is carbon. Where did that carbon come from? It comes from carbon dioxide in the air. People look at trees and think trees grow from the ground. Plants grow from the ground. But if you ask where the substance of the tree comes from, think carefully about where it comes from. Does the tree come from the air? Of course, trees do come from the air. Carbon dioxide in the air enters the tree, changes, kicks out oxygen atoms, forming oxygen and releasing it, leaving carbon atoms. Carbon and water form the substance of the tree. Water comes from the ground, and carbon atoms enter the tree from the air, right? It comes from the sky. Therefore, almost all trees come from the ground. Sorry, I misspoke, they all come from the air. Of course, a small amount comes from underground minerals, etc.

Of course, I told you oxygen atoms... Oxygen atoms and carbon atoms combine very tightly. So how does the tree cleverly absorb carbon dioxide? At this point, the carbon atoms and oxygen atoms are tightly bound, yet the tree can easily break them down? Ah! Life, is it some mysterious power of life? Wrong, it's the sun's rays. Sunlight shines in and separates the oxygen atoms and carbon atoms. Therefore, sunlight is needed for plants to grow. So the role of the sun is to continuously separate oxygen atoms and carbon atoms. Oxygen, as a kind of bad byproduct, is released into the air, leaving behind carbon atoms and water, which form the substance of the tree. Then we put the substance of the tree in the fireplace. The oxygen produced by the tree wants to combine with the carbon in the tree again. Once you heat it to trigger their combination, the whole process will continue. During their vigorous combination, intense thermal motion will occur. Thus, beautiful light and other things appear. It's as if nothing happened; you've turned oxygen and carbon back into carbon dioxide. But light and heat are produced, which are actually the light and heat of the sun radiating in. So when you light a piece of wood, it's like releasing the sun stored in the wood.

The next question is, why is the sun so active and so hot? I'll stop here and leave you with a question to imagine. Most elastic things, like steel bars or springs, are due to forces related to electricity pulling them back. When you bend something, you're pulling the atoms a little farther apart, so these atoms try to come back together. But a rubber band works differently. There are some long chain-like molecules, and some small molecules that are constantly vibrating and hitting these chain molecules. And the chain molecules are all twisted and funny shapes. When you straighten the rubber band, the chain molecules straighten out. But these chain molecules are constantly being hit from the sides. Other atoms try to twist them, making them contract. Therefore, the rubber band tries to contract. It contracts simply due to heat. So if you heat a rubber band, it will contract more. For example, if you hang a heavy object with a rubber band and then bring a lit match close to the rubber band, it's quite interesting to watch the heavy object rise as the rubber band is heated.

You can also prove this point in another way. To prove that it is indeed heat that drives the contraction of a rubber band. When you stretch a rubber band, it's like compressing the piston and internal gas downwards. If you stretch a rubber band, the stretched chain molecules hit other molecules, making them move faster, so the temperature rises. And when you contract the rubber band, the molecules lose some energy when they hit the chain molecules. It's like hitting something soft; it sinks in and "bang bang." Energy is lost. When you pull the piston out, the atoms hit it and their speed decreases, so the temperature drops. So when a gas expands, its temperature decreases.

The interesting thing is that all the phenomena you observe in this world, such as your gas compressing and heating up, expanding and cooling down, or water evaporating from a cup if it's not covered. All these phenomena can be understood using a simple atomic picture. Thinking this way is very interesting. I don't want to take this kind of thinking too seriously. I think we should imagine happily, without any worries. There won't be a teacher asking questions at the end, otherwise it's an annoying subject.

Different atoms want to be close to each other to varying degrees. For example, oxygen atoms in the air want to be close to carbon atoms. If they get too close, they combine vigorously. If they are not very close, they repel each other and separate. So they don't know they can combine. It's like a ball trying to climb a hill. There's a hole in front of it, into which it can fall, like a crater. A deep opening. The ball just circles around it and doesn't fall in. Because when the ball starts to climb the slope, it rolls back. But if you make it go fast enough to pass the critical point, it will fall into the hole. So if something like wood comes into contact with oxygen, and there are carbon atoms in the wood. The oxygen atoms come and hit the carbon atoms, but the temperature isn't high enough. The oxygen atoms run away again. Air always comes and goes, and nothing happens.

If you heat the oxygen atoms in some way to make them faster, to accelerate a few atoms at first, meaning to get them past the critical point. They get close enough to the carbon atoms, and then they combine vigorously. This will produce more vigorous vibrations, possibly hitting other atoms and making them move faster, so they can pass the critical point and hit other carbon atoms. Their continuous vibration causes other atoms to vibrate together, and a terrible disaster occurs. One atom after another vibrates faster and faster, combining vigorously, and everything changes. This "disaster" is fire. This is one way to describe "fire." This collision is constantly happening, never stopping. Once it starts, it continues to do so. The heat produced gives other atoms the ability to collide and produce more heat, causing more atoms to behave the same way. So this vigorous combination triggers a lot of vibration.

If I place those less energetic atoms over there, for example, if I place a cup of cold coffee next to a pile of burning wood. The atoms in the coffee will vibrate vigorously, that's the heat of the fire. Of course, there will be... See, this is what happens when you start thinking, you can't stop at all. You just want to know how it started. Why did the wood stay with the oxygen for so long without fire appearing before? Where did this heat come from? Actually, it comes from the tree. The substance of the tree is carbon. Where did that carbon come from? It comes from carbon dioxide in the air. People look at trees and think trees grow from the ground. Plants grow from the ground. But if you ask where the substance of the tree comes from, think carefully about where it comes from. Does the tree come from the air? Of course, trees do come from the air. Carbon dioxide in the air enters the tree, changes, kicks out oxygen atoms, forming oxygen and releasing it, leaving carbon atoms. Carbon and water form the substance of the tree. Water comes from the ground, and carbon atoms enter the tree from the air, right? It comes from the sky. Therefore, almost all trees come from the ground. Sorry, I misspoke, they all come from the air. Of course, a small amount comes from underground minerals, etc.

Of course, I told you oxygen atoms... Oxygen atoms and carbon atoms combine very tightly. So how does the tree cleverly absorb carbon dioxide? At this point, the carbon atoms and oxygen atoms are tightly bound, yet the tree can easily break them down? Ah! Life, is it some mysterious power of life? Wrong, it's the sun's rays. Sunlight shines in and separates the oxygen atoms and carbon atoms. Therefore, sunlight is needed for plants to grow. So the role of the sun is to continuously separate oxygen atoms and carbon atoms. Oxygen, as a kind of bad byproduct, is released into the air, leaving behind carbon atoms and water, which form the substance of the tree. Then we put the substance of the tree in the fireplace. The oxygen produced by the tree wants to combine with the carbon in the tree again. Once you heat it to trigger their combination, the whole process will continue. During their vigorous combination, intense thermal motion will occur. Thus, beautiful light and other things appear. It's as if nothing happened; you've turned oxygen and carbon back into carbon dioxide. But light and heat are produced, which are actually the light and heat of the sun radiating in. So when you light a piece of wood, it's like releasing the sun stored in the wood.

The next question is, why is the sun so active and so hot? I'll stop here and leave you with a question to imagine. Most elastic things, like steel bars or springs, are due to forces related to electricity pulling them back. When you bend something, you're pulling the atoms a little farther apart, so these atoms try to come back together. But a rubber band works differently. There are some long chain-like molecules, and some small molecules that are constantly vibrating and hitting these chain molecules. And the chain molecules are all twisted and funny shapes. When you straighten the rubber band, the chain molecules straighten out. But these chain molecules are constantly being hit from the sides. Other atoms try to twist them, making them contract. Therefore, the rubber band tries to contract. It contracts simply due to heat. So if you heat a rubber band, it will contract more. For example, if you hang a heavy object with a rubber band and then bring a lit match close to the rubber band, it's quite interesting to watch the heavy object rise as the rubber band is heated.

You can also prove this point in another way. To prove that it is indeed heat that drives the contraction of a rubber band. When you stretch a rubber band, it's like compressing the piston and internal gas downwards. If you stretch a rubber band, the stretched chain molecules hit other molecules, making them move faster, so the temperature rises. And when you contract the rubber band, the molecules lose some energy when they hit the chain molecules. It's like hitting something soft; it sinks in and "bang bang." Energy is lost. When you pull the piston out, the atoms hit it and their speed decreases, so the temperature drops. So when a gas expands, its temperature decreases.

The interesting thing is that all the phenomena you observe in this world, such as your gas compressing and heating up, expanding and cooling down, or water evaporating from a cup if it's not covered. All these phenomena can be understood using a simple atomic picture. Thinking this way is very interesting. I don't want to take this kind of thinking too seriously. I think we should imagine happily, without any worries. There won't be a teacher asking questions at the end, otherwise it's an annoying subject.

Different atoms want to be close to each other to varying degrees. For example, oxygen atoms in the air want to be close to carbon atoms. If they get too close, they combine vigorously. If they are not very close, they repel each other and separate. So they don't know they can combine. It's like a ball trying to climb a hill. There's a hole in front of it, into which it can fall, like a crater. A deep opening. The ball just circles around it and doesn't fall in. Because when the ball starts to climb the slope, it rolls back. But if you make it go fast enough to pass the critical point, it will fall into the hole. So if something like wood comes into contact with oxygen, and there are carbon atoms in the wood. The oxygen atoms come and hit the carbon atoms, but the temperature isn't high enough. The oxygen atoms run away again. Air always comes and goes, and nothing happens.

If you heat the oxygen atoms in some way to make them faster, to accelerate a few atoms at first, meaning to get them past the critical point. They get close enough to the carbon atoms, and then they combine vigorously. This will produce more vigorous vibrations, possibly hitting other atoms and making them move faster, so they can pass the critical point and hit other carbon atoms. Their continuous vibration causes other atoms to vibrate together, and a terrible disaster occurs. One atom after another vibrates faster and faster, combining vigorously, and everything changes. This "disaster" is fire. This is one way to describe "fire." This collision is constantly happening, never stopping. Once it starts, it continues to do so. The heat produced gives other atoms the ability to collide and produce more heat, causing more atoms to behave the same way. So this vigorous combination triggers a lot of vibration.

If I place those less energetic atoms over there, for example, if I place a cup of cold coffee next to a pile of burning wood. The atoms in the coffee will vibrate vigorously, that's the heat of the fire. Of course, there will be... See, this is what happens when you start thinking, you can't stop at all. You just want to know how it started. Why did the wood stay with the oxygen for so long without fire appearing before? Where did this heat come from? Actually, it comes from the tree. The substance of the tree is carbon. Where did that carbon come from? It comes from carbon dioxide in the air. People look at trees and think trees grow from the ground. Plants grow from the ground. But if you ask where the substance of the tree comes from, think carefully about where it comes from. Does the tree come from the air? Of course, trees do come from the air. Carbon dioxide in the air enters the tree, changes, kicks out oxygen atoms, forming oxygen and releasing it, leaving carbon atoms. Carbon and water form the substance of the tree. Water comes from the ground, and carbon atoms enter the tree from the air, right? It comes from the sky. Therefore, almost all trees come from the ground. Sorry, I misspoke, they all come from the air. Of course, a small amount comes from underground minerals, etc.

Of course, I told you oxygen atoms... Oxygen atoms and carbon atoms combine very tightly. So how does the tree cleverly absorb carbon dioxide? At this point, the carbon atoms and oxygen atoms are tightly bound, yet the tree can easily break them down? Ah! Life, is it some mysterious power of life? Wrong, it's the sun's rays. Sunlight shines in and separates the oxygen atoms and carbon atoms. Therefore, sunlight is needed for plants to grow. So the role of the sun is to continuously separate oxygen atoms and carbon atoms. Oxygen, as a kind of bad byproduct, is released into the air, leaving behind carbon atoms and water, which form the substance of the tree. Then we put the substance of the tree in the fireplace. The oxygen produced by the tree wants to combine with the carbon in the tree again. Once you heat it to trigger their combination, the whole process will continue. During their vigorous combination, intense thermal motion will occur. Thus, beautiful light and other things appear. It's as if nothing happened; you've turned oxygen and carbon back into carbon dioxide. But light and heat are produced, which are actually the light and heat of the sun radiating in. So when you light a piece of wood, it's like releasing the sun stored in the wood.

The next question is, why is the sun so active and so hot? I'll stop here and leave you with a question to imagine. Most elastic things, like steel bars or springs, are due to forces related to electricity pulling them back. When you bend something, you're pulling the atoms a little farther apart, so these atoms try to come back together. But a rubber band works differently. There are some long chain-like molecules, and some small molecules that are constantly vibrating and hitting these chain molecules. And the chain molecules are all twisted and funny shapes. When you straighten the rubber band, the chain molecules straighten out. But these chain molecules are constantly being hit from the sides. Other atoms try to twist them, making them contract. Therefore, the rubber band tries to contract. It contracts simply due to heat. So if you heat a rubber band, it will contract more. For example, if you hang a heavy object with a rubber band and then bring a lit match close to the rubber band, it's quite interesting to watch the heavy object rise as the rubber band is heated.

You can also prove this point in another way. To prove that it is indeed heat that drives the contraction of a rubber band. When you stretch a rubber band, it's like compressing the piston and internal gas downwards. If you stretch a rubber band, the stretched chain molecules hit other molecules, making them move faster, so the temperature rises. And when you contract the rubber band, the molecules lose some energy when they hit the chain molecules. It's like hitting something soft; it sinks in and "bang bang." Energy is lost. When you pull the piston out, the atoms hit it and their speed decreases, so the temperature drops. So when a gas expands, its temperature decreases.

The interesting thing is that all the phenomena you observe in this world, such as your gas compressing and heating up, expanding and cooling down, or water evaporating from a cup if it's not covered. All these phenomena can be understood using a simple atomic picture. Thinking this way is very interesting. I don't want to take this kind of thinking too seriously. I think we should imagine happily, without any worries. There won't be a teacher asking questions at the end, otherwise it's an annoying subject.

Different atoms want to be close to each other to varying degrees. For example, oxygen atoms in the air want to be close to carbon atoms. If they get too close, they combine vigorously. If they are not very close, they repel each other and separate. So they don't know they can combine. It's like a ball trying to climb a hill. There's a hole in front of it, into which it can fall, like a crater. A deep opening. The ball just circles around it and doesn't fall in. Because when the ball starts to climb the slope, it rolls back. But if you make it go fast enough to pass the critical point, it will fall into the hole. So if something like wood comes into contact with oxygen, and there are carbon atoms in the wood. The oxygen atoms come and hit the carbon atoms, but the temperature isn't high enough. The oxygen atoms run away again. Air always comes and goes, and nothing happens.

If you heat the oxygen atoms in some way to make them faster, to accelerate a few atoms at first, meaning to get them past the critical point. They get close enough to the carbon atoms, and then they combine vigorously. This will produce more vigorous vibrations, possibly hitting other atoms and making them move faster, so they can pass the critical point and hit other carbon atoms. Their continuous vibration causes other atoms to vibrate together, and a terrible disaster occurs. One atom after another vibrates faster and faster, combining vigorously, and everything changes. This "disaster" is fire. This is one way to describe "fire." This collision is constantly happening, never stopping. Once it starts, it continues to do so. The heat produced gives other atoms the ability to collide and produce more heat, causing more atoms to behave the same way. So this vigorous combination triggers a lot of vibration.

If I place those less energetic atoms over there, for example, if I place a cup of cold coffee next to a pile of burning wood. The atoms in the coffee will vibrate vigorously, that's the heat of the fire. Of course, there will be... See, this is what happens when you start thinking, you can't stop at all. You just want to know how it started. Why did the wood stay with the oxygen for so long without fire appearing before? Where did this heat come from? Actually, it comes from the tree. The substance of the tree is carbon. Where did that carbon come from? It comes from carbon dioxide in the air. People look at trees and think trees grow from the ground. Plants grow from the ground. But if you ask where the substance of the tree comes from, think carefully about where it comes from. Does the tree come from the air? Of course, trees do come from the air. Carbon dioxide in the air enters the tree, changes, kicks out oxygen atoms, forming oxygen and releasing it, leaving carbon atoms. Carbon and water form the substance of the tree. Water comes from the ground, and carbon atoms enter the tree from the air, right? It comes from the sky. Therefore, almost all trees come from the ground. Sorry, I misspoke, they all come from the air. Of course, a small amount comes from underground minerals, etc.

Of course, I told you oxygen atoms... Oxygen atoms and carbon atoms combine very tightly. So how does the tree cleverly absorb carbon dioxide? At this point, the carbon atoms and oxygen atoms are tightly bound, yet the tree can easily break them down? Ah! Life, is it some mysterious power of life? Wrong, it's the sun's rays. Sunlight shines in and separates the oxygen atoms and carbon atoms. Therefore, sunlight is needed for plants to grow. So the role of the sun is to continuously separate oxygen atoms and carbon atoms. Oxygen, as a kind of bad byproduct, is released into the air, leaving behind carbon atoms and water, which form the substance of the tree. Then we put the substance of the tree in the fireplace. The oxygen produced by the tree wants to combine with the carbon in the tree again. Once you heat it to trigger their combination, the whole process will continue. During their vigorous combination, intense thermal motion will occur. Thus, beautiful light and other things appear. It's as if nothing happened; you've turned oxygen and carbon back into carbon dioxide. But light and heat are produced, which are actually the light and heat of the sun radiating in. So when you light a piece of wood, it's like releasing the sun stored in the wood.

The next question is, why is the sun so active and so hot? I'll stop here and leave you with a question to imagine. Most elastic things, like steel bars or springs, are due to forces related to electricity pulling them back. When you bend something, you're pulling the atoms a little farther apart, so these atoms try to come back together. But a rubber band works differently. There are some long chain-like molecules, and some small molecules that are constantly vibrating and hitting these chain molecules. And the chain molecules are all twisted and funny shapes. When you straighten the rubber band, the chain molecules straighten out. But these chain molecules are constantly being hit from the sides. Other atoms try to twist them, making them contract. Therefore, the rubber band tries to contract. It contracts simply due to heat. So if you heat a rubber band, it will contract more. For example, if you hang a heavy object with a rubber band and then bring a lit match close to the rubber band, it's quite interesting to watch the heavy object rise as the rubber band is heated.

You can also prove this point in another way. To prove that it is indeed heat that drives the contraction of a rubber band. When you stretch a rubber band, it's like compressing the piston and internal gas downwards. If you stretch a rubber band, the stretched chain molecules hit other molecules, making them move faster, so the temperature rises. And when you contract the rubber band, the molecules lose some energy when they hit the chain molecules. It's like hitting something soft; it sinks in and "bang bang." Energy is lost. When you pull the piston out, the atoms hit it and their speed decreases, so the temperature drops. So when a gas expands, its temperature decreases.

The interesting thing is that all the phenomena you observe in this world, such as your gas compressing and heating up, expanding and cooling down, or water evaporating from a cup if it's not covered. All these phenomena can be understood using a simple atomic picture. Thinking this way is very interesting. I don't want to take this kind of thinking too seriously. I think we should imagine happily, without any worries. There won't be a teacher asking questions at the end, otherwise it's an annoying subject.

Different atoms want to be close to each other to varying degrees. For example, oxygen atoms in the air want to be close to carbon atoms. If they get too close, they combine vigorously. If they are not very close, they repel each other and separate. So they don't know they can combine. It's like a ball trying to climb a hill. There's a hole in front of it, into which it can fall, like a crater. A deep opening. The ball just circles around it and doesn't fall in. Because when the ball starts to climb the slope, it rolls back. But if you make it go fast enough to pass the critical point, it will fall into the hole. So if something like wood comes into contact with oxygen, and there are carbon atoms in the wood. The oxygen atoms come and hit the carbon atoms, but the temperature isn't high enough. The oxygen atoms run away again. Air always comes and goes, and nothing happens.

If you heat the oxygen atoms in some way to make them faster, to accelerate a few atoms at first, meaning to get them past the critical point. They get close enough to the carbon atoms, and then they combine vigorously. This will produce more vigorous vibrations, possibly hitting other atoms and making them move faster, so they can pass the critical point and hit other carbon atoms. Their continuous vibration causes other atoms to vibrate together, and a terrible disaster occurs. One atom after another vibrates faster and faster, combining vigorously, and everything changes. This "disaster" is fire. This is one way to describe "fire." This collision is constantly happening, never stopping. Once it starts, it continues to do so. The heat produced gives other atoms the ability to collide and produce more heat, causing more atoms to behave the same way. So this vigorous combination triggers a lot of vibration.

If I place those less energetic atoms over there, for example, if I place a cup of cold coffee next to a pile of burning wood. The atoms in the coffee will vibrate vigorously, that's the heat of the fire. Of course, there will be... See, this is what happens when you start thinking, you can't stop at all. You just want to know how it started. Why did the wood stay with the oxygen for so long without fire appearing before? Where did this heat come from? Actually, it comes from the tree. The substance of the tree is carbon. Where did that carbon come from? It comes from carbon dioxide in the air. People look at trees and think trees grow from the ground. Plants grow from the ground. But if you ask where the substance of the tree comes from, think carefully about where it comes from. Does the tree come from the air? Of course, trees do come from the air. Carbon dioxide in the air enters the tree, changes, kicks out oxygen atoms, forming oxygen and releasing it, leaving carbon atoms. Carbon and water form the substance of the tree. Water comes from the ground, and carbon atoms enter the tree from the air, right? It comes from the sky. Therefore, almost all trees come from the ground. Sorry, I misspoke, they all come from the air. Of course, a small amount comes from underground minerals, etc.

Of course, I told you oxygen atoms... Oxygen atoms and carbon atoms combine very tightly. So how does the tree cleverly absorb carbon dioxide? At this point, the carbon atoms and oxygen atoms are tightly bound, yet the tree can easily break them down? Ah! Life, is it some mysterious power of life? Wrong, it's the sun's rays. Sunlight shines in and separates the oxygen atoms and carbon atoms. Therefore, sunlight is needed for plants to grow. So the role of the sun is to continuously separate oxygen atoms and carbon atoms. Oxygen, as a kind of bad byproduct, is released into the air, leaving behind carbon atoms and water, which form the substance of the tree. Then we put the substance of the tree in the fireplace. The oxygen produced by the tree wants to combine with the carbon in the tree again. Once you heat it to trigger their combination, the whole process will continue. During their vigorous combination, intense thermal motion will occur. Thus, beautiful light and other things appear. It's as if nothing happened; you've turned oxygen and carbon back into carbon dioxide. But light and heat are produced, which are actually the light and heat of the sun radiating in. So when you light a piece of wood, it's like releasing the sun stored in the wood.

The next question is, why is the sun so active and so hot? I'll stop here and leave you with a question to imagine. Most elastic things, like steel bars or springs, are due to forces related to electricity pulling them back. When you bend something, you're pulling the atoms a little farther apart, so these atoms try to come back together. But a rubber band works differently. There are some long chain-like molecules, and some small molecules that are constantly vibrating and hitting these chain molecules. And the chain molecules are all twisted and funny shapes. When you straighten the rubber band, the chain molecules straighten out. But these chain molecules are constantly being hit from the sides. Other atoms try to twist them, making them contract. Therefore, the rubber band tries to contract. It contracts simply due to heat. So if you heat a rubber band, it will contract more. For example, if you hang a heavy object with a rubber band and then bring a lit match close to the rubber band, it's quite interesting to watch the heavy object rise as the rubber band is heated.

You can also prove this point in another way. To prove that it is indeed heat that drives the contraction of a rubber band. When you stretch a rubber band, it's like compressing the piston and internal gas downwards. If you stretch a rubber band, the stretched chain molecules hit other molecules, making them move faster, so the temperature rises. And when you contract the rubber band, the molecules lose some energy when they hit the chain molecules. It's like hitting something soft; it sinks in and "bang bang." Energy is lost. When you pull the piston out, the atoms hit it and their speed decreases, so the temperature drops. So when a gas expands, its temperature decreases.

The interesting thing is that all the phenomena you observe in this world, such as your gas compressing and heating up, expanding and cooling down, or water evaporating from a cup if it's not covered. All these phenomena can be understood using a simple atomic picture. Thinking this way is very interesting. I don't want to take this kind of thinking too seriously. I think we should imagine happily, without any worries. There won't be a teacher asking questions at the end, otherwise it's an annoying subject.

Different atoms want to be close to each other to varying degrees. For example, oxygen atoms in the air want to be close to carbon atoms. If they get too close, they combine vigorously. If they are not very close, they repel each other and separate. So they don't know they can combine. It's like a ball trying to climb a hill. There's a hole in front of it, into which it can fall, like a crater. A deep opening. The ball just circles around it and doesn't fall in. Because when the ball starts to climb the slope, it rolls back. But if you make it go fast enough to pass the critical point, it will fall into the hole. So if something like wood comes into contact with oxygen, and there are carbon atoms in the wood. The oxygen atoms come and hit the carbon atoms, but the temperature isn't high enough. The oxygen atoms run away again. Air always comes and goes, and nothing happens.

If you heat the oxygen atoms in some way to make them faster, to accelerate a few atoms at first, meaning to get them past the critical point. They get close enough to the carbon atoms, and then they combine vigorously. This will produce more vigorous vibrations, possibly hitting other atoms and making them move faster, so they can pass the critical point and hit other carbon atoms. Their continuous vibration causes other atoms to vibrate together, and a terrible disaster occurs. One atom after another vibrates faster and faster, combining vigorously, and everything changes. This "disaster" is fire. This is one way to describe "fire." This collision is constantly happening, never stopping. Once it starts, it continues to do so. The heat produced gives other atoms the ability to collide and produce more heat, causing more atoms to behave the same way. So this vigorous combination triggers a lot of vibration.

If I place those less energetic atoms over there, for example, if I place a cup of cold coffee next to a pile of burning wood. The atoms in the coffee will vibrate vigorously, that's the heat of the fire. Of course, there will be... See, this is what happens when you start thinking, you can't stop at all. You just want to know how it started. Why did the wood stay with the oxygen for so long without fire appearing before? Where did this heat come from? Actually, it comes from the tree. The substance of the tree is carbon. Where did that carbon come from? It comes from carbon dioxide in the air. People look at trees and think trees grow from the ground. Plants grow from the ground. But if you ask where the substance of the tree comes from, think carefully about where it comes from. Does the tree come from the air? Of course, trees do come from the air. Carbon dioxide in the air enters the tree, changes, kicks out oxygen atoms, forming oxygen and releasing it, leaving carbon atoms. Carbon and water form the substance of the tree. Water comes from the ground, and carbon atoms enter the tree from the air, right? It comes from the sky. Therefore, almost all trees come from the ground. Sorry, I misspoke, they all come from the air. Of course, a small amount comes from underground minerals, etc.

Of course, I told you oxygen atoms... Oxygen atoms and carbon atoms combine very tightly. So how does the tree cleverly absorb carbon dioxide? At this point, the carbon atoms and oxygen atoms are tightly bound, yet the tree can easily break them down? Ah! Life, is it some mysterious power of life? Wrong, it's the sun's rays. Sunlight shines in and separates the oxygen atoms and carbon atoms. Therefore, sunlight is needed for plants to grow. So the role of the sun is to continuously separate oxygen atoms and carbon atoms. Oxygen, as a kind of bad byproduct, is released into the air, leaving behind carbon atoms and water, which form the substance of the tree. Then we put the substance of the tree in the fireplace. The oxygen produced by the tree wants to combine with the carbon in the tree again. Once you heat it to trigger their combination, the whole process will continue. During their vigorous combination, intense thermal motion will occur. Thus, beautiful light and other things appear. It's as if nothing happened; you've turned oxygen and carbon back into carbon dioxide. But light and heat are produced, which are actually the light and heat of the sun radiating in. So when you light a piece of wood, it's like releasing the sun stored in the wood.

The next question is, why is the sun so active and so hot? I'll stop here and leave you with a question to imagine. Most elastic things, like steel bars or springs, are due to forces related to electricity pulling them back. When you bend something, you're pulling the atoms a little farther apart, so these atoms try to come back together. But a rubber band works differently. There are some long chain-like molecules, and some small molecules that are constantly vibrating and hitting these chain molecules. And the chain molecules are all twisted and funny shapes. When you straighten the rubber band, the chain molecules straighten out. But these chain molecules are constantly being hit from the sides. Other atoms try to twist them, making them contract. Therefore, the rubber band tries to contract. It contracts simply due to heat. So if you heat a rubber band, it will contract more. For example, if you hang a heavy object with a rubber band and then bring a lit match close to the rubber band, it's quite interesting to watch the heavy object rise as the rubber band is heated.

You can also prove this point in another way. To prove that it is indeed heat that drives the contraction of a rubber band. When you stretch a rubber band, it's like compressing the piston and internal gas downwards. If you stretch a rubber band, the stretched chain molecules hit other molecules, making them move faster, so the temperature rises. And when you contract the rubber band, the molecules lose some energy when they hit the chain molecules. It's like hitting something soft; it sinks in and "bang bang." Energy is lost. When you pull the piston out, the atoms hit it and their speed decreases, so the temperature drops. So when a gas expands, its temperature decreases.

The interesting thing is that all the phenomena you observe in this world, such as your gas compressing and heating up, expanding and cooling down, or water evaporating from a cup if it's not covered. All these phenomena can be understood using a simple atomic picture. Thinking this way is very interesting. I don't want to take this kind of thinking too seriously. I think we should imagine happily, without any worries. There won't be a teacher asking questions at the end, otherwise it's an annoying subject.

Different atoms want to be close to each other to varying degrees. For example, oxygen atoms in the air want to be close to carbon atoms. If they get too close, they combine vigorously. If they are not very close, they repel each other and separate. So they don't know they can combine. It's like a ball trying to climb a hill. There's a hole in front of it, into which it can fall, like a crater. A deep opening. The ball just circles around it and doesn't fall in. Because when the ball starts to climb the slope, it rolls back. But if you make it go fast enough to pass the critical point, it will fall into the hole. So if something like wood comes into contact with oxygen, and there are carbon atoms in the wood. The oxygen atoms come and hit the carbon atoms, but the temperature isn't high enough. The oxygen atoms run away again. Air always comes and goes, and nothing happens.

If you heat the oxygen atoms in some way to make them faster, to accelerate a few atoms at first, meaning to get them past the critical point. They get close enough to the carbon atoms, and then they combine vigorously. This will produce more vigorous vibrations, possibly hitting other atoms and making them move faster, so they can pass the critical point and hit other carbon atoms. Their continuous vibration causes other atoms to vibrate together, and a terrible disaster occurs. One atom after another vibrates faster and faster, combining vigorously, and everything changes. This "disaster" is fire. This is one way to describe "fire." This collision is constantly happening, never stopping. Once it starts, it continues to do so. The heat produced gives other atoms the ability to collide and produce more heat, causing more atoms to behave the same way. So this vigorous combination triggers a lot of vibration.

If I place those less energetic atoms over there, for example, if I place a cup of cold coffee next to a pile of burning wood. The atoms in the coffee will vibrate vigorously, that's the heat of the fire. Of course, there will be... See, this is what happens when you start thinking, you can't stop at all. You just want to know how it started. Why did the wood stay with the oxygen for so long without fire appearing before? Where did this heat come from? Actually, it comes from the tree. The substance of the tree is carbon. Where did that carbon come from? It comes from carbon dioxide in the air. People look at trees and think trees grow from the ground. Plants grow from the ground. But if you ask where the substance of the tree comes from, think carefully about where it comes from. Does the tree come from the air? Of course, trees do come from the air. Carbon dioxide in the air enters the tree, changes, kicks out oxygen atoms, forming oxygen and releasing it, leaving carbon atoms. Carbon and water form the substance of the tree. Water comes from the ground, and carbon atoms enter the tree from the air, right? It comes from the sky. Therefore, almost all trees come from the ground. Sorry, I misspoke, they all come from the air. Of course, a small amount comes from underground minerals, etc.

Of course, I told you oxygen atoms... Oxygen atoms and carbon atoms combine very tightly. So how does the tree cleverly absorb carbon dioxide? At this point, the carbon atoms and oxygen atoms are tightly bound, yet the tree can easily break them down? Ah! Life, is it some mysterious power of life? Wrong, it's the sun's rays. Sunlight shines in and separates the oxygen atoms and carbon atoms. Therefore, sunlight is needed for plants to grow. So the role of the sun is to continuously separate oxygen atoms and carbon atoms. Oxygen, as a kind of bad byproduct, is released into the air, leaving behind carbon atoms and water, which form the substance of the tree. Then we put the substance of the tree in the fireplace. The oxygen produced by the tree wants to combine with the carbon in the tree again. Once you heat it to trigger their combination, the whole process will continue. During their vigorous combination, intense thermal motion will occur. Thus, beautiful light and other things appear. It's as if nothing happened; you've turned oxygen and carbon back into carbon dioxide. But light and heat are produced, which are actually the light and heat of the sun radiating in. So when you light a piece of wood, it's like releasing the sun stored in the wood.

The next question is, why is the sun so active and so hot? I'll stop here and leave you with a question to imagine. Most elastic things, like steel bars or springs, are due to forces related to electricity pulling them back. When you bend something, you're pulling the atoms a little farther apart, so these atoms try to come back together. But a rubber band works differently. There are some long chain-like molecules, and some small molecules that are constantly vibrating and hitting these chain molecules. And the chain molecules are all twisted and funny shapes. When you straighten the rubber band, the chain molecules straighten out. But these chain molecules are constantly being hit from the sides. Other atoms try to twist them, making them contract. Therefore, the rubber band tries to contract. It contracts simply due to heat. So if you heat a rubber band, it will contract more. For example, if you hang a heavy object with a rubber band and then bring a lit match close to the rubber band, it's quite interesting to watch the heavy object rise as the rubber band is heated.

You can also prove this point in another way. To prove that it is indeed heat that drives the contraction of a rubber band. When you stretch a rubber band, it's like compressing the piston and internal gas downwards. If you stretch a rubber band, the stretched chain molecules hit other molecules, making them move faster, so the temperature rises. And when you contract the rubber band, the molecules lose some energy when they hit the chain molecules. It's like hitting something soft; it sinks in and "bang bang." Energy is lost. When you pull the piston out, the atoms hit it and their speed decreases, so the temperature drops. So when a gas expands, its temperature decreases.

The interesting thing is that all the phenomena you observe in this world, such as your gas compressing and heating up, expanding and cooling down, or water evaporating from a cup if it's not covered. All these phenomena can be understood using a simple atomic picture. Thinking this way is very interesting. I don't want to take this kind of thinking too seriously. I think we should imagine happily, without any worries. There won't be a teacher asking questions at the end, otherwise it's an annoying subject.

Different atoms want to be close to each other to varying degrees. For example, oxygen atoms in the air want to be close to carbon atoms. If they get too close, they combine vigorously. If they are not very close, they repel each other and separate. So they don't know they can combine. It's like a ball trying to climb a hill. There's a hole in front of it, into which it can fall, like a crater. A deep opening. The ball just circles around it and doesn't fall in. Because when the ball starts to climb the slope, it rolls back. But if you make it go fast enough to pass the critical point, it will fall into the hole. So if something like wood comes into contact with oxygen, and there are carbon atoms in the wood. The oxygen atoms come and hit the carbon atoms, but the temperature isn't high enough. The oxygen atoms run away again. Air always comes and goes, and nothing happens.

If you heat the oxygen atoms in some way to make them faster, to accelerate a few atoms at first, meaning to get them past the critical point. They get close enough to the carbon atoms, and then they combine vigorously. This will produce more vigorous vibrations, possibly hitting other atoms and making them move faster, so they can pass the critical point and hit other carbon atoms. Their continuous vibration causes other atoms to vibrate together, and a terrible disaster occurs. One atom after another vibrates faster and faster, combining vigorously, and everything changes. This "disaster" is fire. This is one way to describe "fire." This collision is constantly happening, never stopping. Once it starts, it continues to do so. The heat produced gives other atoms the ability to collide and produce more heat, causing more atoms to behave the same way. So this vigorous combination triggers a lot of vibration.

If I place those less energetic atoms over there, for example, if I place a cup of cold coffee next to a pile of burning wood. The atoms in the coffee will vibrate vigorously, that's the heat of the fire. Of course, there will be... See, this is what happens when you start thinking, you can't stop at all. You just want to know how it started. Why did the wood stay with the oxygen for so long without fire appearing before? Where did this heat come from? Actually, it comes from the tree. The substance of the tree is carbon. Where did that carbon come from? It comes from carbon dioxide in the air. People look at trees and think trees grow from the ground. Plants grow from the ground. But if you ask where the substance of the tree comes from, think carefully about where it comes from. Does the tree come from the air? Of course, trees do come from the air. Carbon dioxide in the air enters the tree, changes, kicks out oxygen atoms, forming oxygen and releasing it, leaving carbon atoms. Carbon and water form the substance of the tree. Water comes from the ground, and carbon atoms enter the tree from the air, right? It comes from the sky. Therefore, almost all trees come from the ground. Sorry, I misspoke, they all come from the air. Of course, a small amount comes from underground minerals, etc.

Of course, I told you oxygen atoms... Oxygen atoms and carbon atoms combine very tightly. So how does the tree cleverly absorb carbon dioxide? At this point, the carbon atoms and oxygen atoms are tightly bound, yet the tree can easily break them down? Ah! Life, is it some mysterious power of life? Wrong, it's the sun's rays. Sunlight shines in and separates the oxygen atoms and carbon atoms. Therefore, sunlight is needed for plants to grow. So the role of the sun is to continuously separate oxygen atoms and carbon atoms. Oxygen, as a kind of bad byproduct, is released into the air, leaving behind carbon atoms and water, which form the substance of the tree. Then we put the substance of the tree in the fireplace. The oxygen produced by the tree wants to combine with the carbon in the tree again. Once you heat it to trigger their combination, the whole process will continue. During their vigorous combination, intense thermal motion will occur. Thus, beautiful light and other things appear. It's as if nothing happened; you've turned oxygen and carbon back into carbon dioxide. But light and heat are produced, which are actually the light and heat of the sun radiating in. So when you light a piece of wood, it's like releasing the sun stored in the wood.

The next question is, why is the sun so active and so hot? I'll stop here and leave you with a question to imagine. Most elastic things, like steel bars or springs, are due to forces related to electricity pulling them back. When you bend something, you're pulling the atoms a little farther apart, so these atoms try to come back together. But a rubber band works differently. There are some long chain-like molecules, and some small molecules that are constantly vibrating and hitting these chain molecules. And the chain molecules are all twisted and funny shapes. When you straighten the rubber band, the chain molecules straighten out. But these chain molecules are constantly being hit from the sides. Other atoms try to twist them, making them contract. Therefore, the rubber band tries to contract. It contracts simply due to heat. So if you heat a rubber band, it will contract more. For example, if you hang a heavy object with a rubber band and then bring a lit match close to the rubber band, it's quite interesting to watch the heavy object rise as the rubber band is heated.

You can also prove this point in another way. To prove that it is indeed heat that drives the contraction of a rubber band. When you stretch a rubber band, it's like compressing the piston and internal gas downwards. If you stretch a rubber band, the stretched chain molecules hit other molecules, making them move faster, so the temperature rises. And when you contract the rubber band, the molecules lose some energy when they hit the chain molecules. It's like hitting something soft; it sinks in and "bang bang." Energy is lost. When you pull the piston out, the atoms hit it and their speed decreases, so the temperature drops. So when a gas expands, its temperature decreases.

The interesting thing is that all the phenomena you observe in this world, such as your gas compressing and heating up, expanding and cooling down, or water evaporating from a cup if it's not covered. All these phenomena can be understood using a simple atomic picture. Thinking this way is very interesting. I don't want to take this kind of thinking too seriously. I think we should imagine happily, without any worries. There won't be a teacher asking questions at the end, otherwise it's an annoying subject.

Different atoms want to be close to each other to varying degrees. For example, oxygen atoms in the air want to be close to carbon atoms. If they get too close, they combine vigorously. If they are not very close, they repel each other and separate. So they don't know they can combine. It's like a ball trying to climb a hill. There's a hole in front of it, into which it can fall, like a crater. A deep opening. The ball just circles around it and doesn't fall in. Because when the ball starts to climb the slope, it rolls back. But if you make it go fast enough to pass the critical point, it will fall into the hole. So if something like wood comes into contact with oxygen, and there are carbon atoms in the wood. The oxygen atoms come and hit the carbon atoms, but the temperature isn't high enough. The oxygen atoms run away again. Air always comes and goes, and nothing happens.

If you heat the oxygen atoms in some way to make them faster, to accelerate a few atoms at first, meaning to get them past the critical point. They get close enough to the carbon atoms, and then they combine vigorously. This will produce more vigorous vibrations, possibly hitting other atoms and making them move faster, so they can pass the critical point and hit other carbon atoms. Their continuous vibration causes other atoms to vibrate together, and a terrible disaster occurs. One atom after another vibrates faster and faster, combining vigorously, and everything changes. This "disaster" is fire. This is one way to describe "fire." This collision is constantly happening, never stopping. Once it starts, it continues to do so. The heat produced gives other atoms the ability to collide and produce more heat, causing more atoms to behave the same way. So this vigorous combination triggers a lot of vibration.

If I place those less energetic atoms over there, for example, if I place a cup of cold coffee next to a pile of burning wood. The atoms in the coffee will vibrate vigorously, that's the heat of the fire. Of course, there will be... See, this is what happens when you start thinking, you can't stop at all. You just want to know how it started. Why did the wood stay with the oxygen for so long without fire appearing before? Where did this heat come from? Actually, it comes from the tree. The substance of the tree is carbon. Where did that carbon come from? It comes from carbon dioxide in the air. People look at trees and think trees grow from the ground. Plants grow from the ground. But if you ask where the substance of the tree comes from, think carefully about where it comes from. Does the tree come from the air? Of course, trees do come from the air. Carbon dioxide in the air enters the tree, changes, kicks out oxygen atoms, forming oxygen and releasing it, leaving carbon atoms. Carbon and water form the substance of the tree. Water comes from the ground, and carbon atoms enter the tree from the air, right? It comes from the sky. Therefore, almost all trees come from the ground. Sorry, I misspoke, they all come from the air. Of course, a small amount comes from underground minerals, etc.

Of course, I told you oxygen atoms... Oxygen atoms and carbon atoms combine very tightly. So how does the tree cleverly absorb carbon dioxide? At this point, the carbon atoms and oxygen atoms are tightly bound, yet the tree can easily break them down? Ah! Life, is it some mysterious power of life? Wrong, it's the sun's rays. Sunlight shines in and separates the oxygen atoms and carbon atoms. Therefore, sunlight is needed for plants to grow. So the role of the sun is to continuously separate oxygen atoms and carbon atoms. Oxygen, as a kind of bad byproduct, is released into the air, leaving behind carbon atoms and water, which form the substance of the tree. Then we put the substance of the tree in the fireplace. The oxygen produced by the tree wants to combine with the carbon in the tree again. Once you heat it to trigger their combination, the whole process will continue. During their vigorous combination, intense thermal motion will occur. Thus, beautiful light and other things appear. It's as if nothing happened; you've turned oxygen and carbon back into carbon dioxide. But light and heat are produced, which are actually the light and heat of the sun radiating in. So when you light a piece of wood, it's like releasing the sun stored in the wood.

The next question is, why is the sun so active and so hot? I'll stop here and leave you with a question to imagine. Most elastic things, like steel bars or springs, are due to forces related to electricity pulling them back. When you bend something, you're pulling the atoms a little farther apart, so these atoms try to come back together. But a rubber band works differently. There are some long chain-like molecules, and some small molecules that are constantly vibrating and hitting these chain molecules. And the chain molecules are all twisted and funny shapes. When you straighten the rubber band, the chain molecules straighten out. But these chain molecules are constantly being hit from the sides. Other atoms try to twist them, making them contract. Therefore, the rubber band tries to contract. It contracts simply due to heat. So if you heat a rubber band, it will contract more. For example, if you hang a heavy object with a rubber band and then bring a lit match close to the rubber band, it's quite interesting to watch the heavy object rise as the rubber band is heated.

You can also prove this point in another way. To prove that it is indeed heat that drives the contraction of a rubber band. When you stretch a rubber band, it's like compressing the piston and internal gas downwards. If you stretch a rubber band, the stretched chain molecules hit other molecules, making them move faster, so the temperature rises. And when you contract the rubber band, the molecules lose some energy when they hit the chain molecules. It's like hitting something soft; it sinks in and "bang bang." Energy is lost. When you pull the piston out, the atoms hit it and their speed decreases, so the temperature drops. So when a gas expands, its temperature decreases.

The interesting thing is that all the phenomena you observe in this world, such as your gas compressing and heating up, expanding and cooling down, or water evaporating from a cup if it's not covered. All these phenomena can be understood using a simple atomic picture. Thinking this way is very interesting. I don't want to take this kind of thinking too seriously. I think we should imagine happily, without any worries. There won't be a teacher asking questions at the end, otherwise it's an annoying subject.

Different atoms want to be close to each other to varying degrees. For example, oxygen atoms in the air want to be close to carbon atoms. If they get too close, they combine vigorously. If they are not very close, they repel each other and separate. So they don't know they can combine. It's like a ball trying to climb a hill. There's a hole in front of it, into which it can fall, like a crater. A deep opening. The ball just circles around it and doesn't fall in. Because when the ball starts to climb the slope, it rolls back. But if you make it go fast enough to pass the critical point, it will fall into the hole. So if something like wood comes into contact with oxygen, and there are carbon atoms in the wood. The oxygen atoms come and hit the carbon atoms, but the temperature isn't high enough. The oxygen atoms run away again. Air always comes and goes, and nothing happens.

If you heat the oxygen atoms in some way to make them faster, to accelerate a few atoms at first, meaning to get them past the critical point. They get close enough to the carbon atoms, and then they combine vigorously. This will produce more vigorous vibrations, possibly hitting other atoms and making them move faster, so they can pass the critical point and hit other carbon atoms. Their continuous vibration causes other atoms to vibrate together, and a terrible disaster occurs. One atom after another vibrates faster and faster, combining vigorously, and everything changes. This "disaster" is fire. This is one way to describe "fire." This collision is constantly happening, never stopping. Once it starts, it continues to do so. The heat produced gives other atoms the ability to collide and produce more heat, causing more atoms to behave the same way. So this vigorous combination triggers a lot of vibration.

If I place those less energetic atoms over there, for example, if I place a cup of cold coffee next to a pile of burning wood. The atoms in the coffee will vibrate vigorously, that's the heat of the fire. Of course, there will be... See, this is what happens when you start thinking, you can't stop at all. You just want to know how it started. Why did the wood stay with the oxygen for so long without fire appearing before? Where did this heat come from? Actually, it comes from the tree. The substance of the tree is carbon. Where did that carbon come from? It comes from carbon dioxide in the air. People look at trees and think trees grow from the ground. Plants grow from the ground. But if you ask where the substance of the tree comes from, think carefully about where it comes from. Does the tree come from the air? Of course, trees do come from the air. Carbon dioxide in the air enters the tree, changes, kicks out oxygen atoms, forming oxygen and releasing it, leaving carbon atoms. Carbon and water form the substance of the tree. Water comes from the ground, and carbon atoms enter the tree from the air, right? It comes from the sky. Therefore, almost all trees come from the ground. Sorry, I misspoke, they all come from the air. Of course, a small amount comes from underground minerals, etc.

Of course, I told you oxygen atoms... Oxygen atoms and carbon atoms combine very tightly. So how does the tree cleverly absorb carbon dioxide? At this point, the carbon atoms and oxygen atoms are tightly bound, yet the tree can easily break them down? Ah! Life, is it some mysterious power of life? Wrong, it's the sun's rays. Sunlight shines in and separates the oxygen atoms and carbon atoms. Therefore, sunlight is needed for plants to grow. So the role of the sun is to continuously separate oxygen atoms and carbon atoms. Oxygen, as a kind of bad byproduct, is released into the air, leaving behind carbon atoms and water, which form the substance of the tree. Then we put the substance of the tree in the fireplace. The oxygen produced by the tree wants to combine with the carbon in the tree again. Once you heat it to trigger their combination, the whole process will continue. During their vigorous combination, intense thermal motion will occur. Thus, beautiful light and other things appear. It's as if nothing happened; you've turned oxygen and carbon back into carbon dioxide. But light and heat are produced, which are actually the light and heat of the sun radiating in. So when you light a piece of wood, it's like releasing the sun stored in the wood.

The next question is, why is the sun so active and so hot? I'll stop here and leave you with a question to imagine. Most elastic things, like steel bars or springs, are due to forces related to electricity pulling them back. When you bend something, you're pulling the atoms a little farther apart, so these atoms try to come back together. But a rubber band works differently. There are some long chain-like molecules, and some small molecules that are constantly vibrating and hitting these chain molecules. And the chain molecules are all twisted and funny shapes. When you straighten the rubber band, the chain molecules straighten out. But these chain molecules are constantly being hit from the sides. Other atoms try to twist them, making them contract. Therefore, the rubber band tries to contract. It contracts simply due to heat. So if you heat a rubber band, it will contract more. For example, if you hang a heavy object with a rubber band and then bring a lit match close to the rubber band, it's quite interesting to watch the heavy object rise as the rubber band is heated.

You can also prove this point in another way. To prove that it is indeed heat that drives the contraction of a rubber band. When you stretch a rubber band, it's like compressing the piston and internal gas downwards. If you stretch a rubber band, the stretched chain molecules hit other molecules, making them move faster, so the temperature rises. And when you contract the rubber band, the molecules lose some energy when they hit the chain molecules. It's like hitting something soft; it sinks in and "bang bang." Energy is lost. When you pull the piston out, the atoms hit it and their speed decreases, so the temperature drops. So when a gas expands, its temperature decreases.

The interesting thing is that all the phenomena you observe in this world, such as your gas compressing and heating up, expanding and cooling down, or water evaporating from a cup if it's not covered. All these phenomena can be understood using a simple atomic picture. Thinking this way is very interesting. I don't want to take this kind of thinking too seriously. I think we should imagine happily, without any worries. There won't be a teacher asking questions at the end, otherwise it's an annoying subject.

Different atoms want to be close to each other to varying degrees. For example, oxygen atoms in the air want to be close to carbon atoms. If they get too close, they combine vigorously. If they are not very close, they repel each other and separate. So they don't know they can combine. It's like a ball trying to climb a hill. There's a hole in front of it, into which it can fall, like a crater. A deep opening. The ball just circles around it and doesn't fall in. Because when the ball starts to climb the slope, it rolls back. But if you make it go fast enough to pass the critical point, it will fall into the hole. So if something like wood comes into contact with oxygen, and there are carbon atoms in the wood. The oxygen atoms come and hit the carbon atoms, but the temperature isn't high enough. The oxygen atoms run away again. Air always comes and goes, and nothing happens.

If you heat the oxygen atoms in some way to make them faster, to accelerate a few atoms at first, meaning to get them past the critical point. They get close enough to the carbon atoms, and then they combine vigorously. This will produce more vigorous vibrations, possibly hitting other atoms and making them move faster, so they can pass the critical point and hit other carbon atoms. Their continuous vibration causes other atoms to vibrate together, and a terrible disaster occurs. One atom after another vibrates faster and faster, combining vigorously, and everything changes. This "disaster" is fire. This is one way to describe "fire." This collision is constantly happening, never stopping. Once it starts, it continues to do so. The heat produced gives other atoms the ability to collide and produce more heat, causing more atoms to behave the same way. So this vigorous combination triggers a lot of vibration.

If I place those less energetic atoms over there, for example, if I place a cup of cold coffee next to a pile of burning wood. The atoms in the coffee will vibrate vigorously, that's the heat of the fire. Of course, there will be... See, this is what happens when you start thinking, you can't stop at all. You just want to know how it started. Why did the wood stay with the oxygen for so long without fire appearing before? Where did this heat come from? Actually, it comes from the tree. The substance of the tree is carbon. Where did that carbon come from? It comes from carbon dioxide in the air. People look at trees and think trees grow from the ground. Plants grow from the ground. But if you ask where the substance of the tree comes from, think carefully about where it comes from. Does the tree come from the air? Of course, trees do come from the air. Carbon dioxide in the air enters the tree, changes, kicks out oxygen atoms, forming oxygen and releasing it, leaving carbon atoms. Carbon and water form the substance of the tree. Water comes from the ground, and carbon atoms enter the tree from the air, right? It comes from the sky. Therefore, almost all trees come from the ground. Sorry, I misspoke, they all come from the air. Of course, a small amount comes from underground minerals, etc.

Of course, I told you oxygen atoms... Oxygen atoms and carbon atoms combine very tightly. So how does the tree cleverly absorb carbon dioxide? At this point, the carbon atoms and oxygen atoms are tightly bound, yet the tree can easily break them down? Ah! Life, is it some mysterious power of life? Wrong, it's the sun's rays. Sunlight shines in and separates the oxygen atoms and carbon atoms. Therefore, sunlight is needed for plants to grow. So the role of the sun is to continuously separate oxygen atoms and carbon atoms. Oxygen, as a kind of bad byproduct, is released into the air, leaving behind carbon atoms and water, which form the substance of the tree. Then we put the substance of the tree in the fireplace. The oxygen produced by the tree wants to combine with the carbon in the tree again. Once you heat it to trigger their combination, the whole process will continue. During their vigorous combination, intense thermal motion will occur. Thus, beautiful light and other things appear. It's as if nothing happened; you've turned oxygen and carbon back into carbon dioxide. But light and heat are produced, which are actually the light and heat of the sun radiating in. So when you light a piece of wood, it's like releasing the sun stored in the wood.

The next question is, why is the sun so active and so hot? I'll stop here and leave you with a question to imagine. Most elastic things, like steel bars or springs, are due to forces related to electricity pulling them back. When you bend something, you're pulling the atoms a little farther apart, so these atoms try to come back together. But a rubber band works differently. There are some long chain-like molecules, and some small molecules that are constantly vibrating and hitting these chain molecules. And the chain molecules are all twisted and funny shapes. When you straighten the rubber band, the chain molecules straighten out. But these chain molecules are constantly being hit from the sides. Other atoms try to twist them, making them contract. Therefore, the rubber band tries to contract. It contracts simply due to heat. So if you heat a rubber band, it will contract more. For example, if you hang a heavy object with a rubber band and then bring a lit match close to the rubber band, it's quite interesting to watch the heavy object rise as the rubber band is heated.

You can also prove this point in another way. To prove that it is indeed heat that drives the contraction of a rubber band. When you stretch a rubber band, it's like compressing the piston and internal gas downwards. If you stretch a rubber band, the stretched chain molecules hit other molecules, making them move faster, so the temperature rises. And when you contract the rubber band, the molecules lose some energy when they hit the chain molecules. It's like hitting something soft; it sinks in and "bang bang." Energy is lost. When you pull the piston out, the atoms hit it and their speed decreases, so the temperature drops. So when a gas expands, its temperature decreases.

The interesting thing is that all the phenomena you observe in this world, such as your gas compressing and heating up, expanding and cooling down, or water evaporating from a cup if it's not covered. All these phenomena can be understood using a simple atomic picture. Thinking this way is very interesting. I don't want to take this kind of thinking too seriously. I think we should imagine happily, without any worries. There won't be a teacher asking questions at the end, otherwise it's an annoying subject.

Different atoms want to be close to each other to varying degrees. For example, oxygen atoms in the air want to be close to carbon atoms. If they get too close, they combine vigorously. If they are not very close, they repel each other and separate. So they don't know they can combine. It's like a ball trying to climb a hill. There's a hole in front of it, into which it can fall, like a crater. A deep opening. The ball just circles around it and doesn't fall in. Because when the ball starts to climb the slope, it rolls back. But if you make it go fast enough to pass the critical point, it will fall into the hole. So if something like wood comes into contact with oxygen, and there are carbon atoms in the wood. The oxygen atoms come and hit the carbon atoms, but the temperature isn't high enough. The oxygen atoms run away again. Air always comes and goes, and nothing happens.

If you heat the oxygen atoms in some way to make them faster, to accelerate a few atoms at first, meaning to get them past the critical point. They get close enough to the carbon atoms, and then they combine vigorously. This will produce more vigorous vibrations, possibly hitting other atoms and making them move faster, so they can pass the critical point and hit other carbon atoms. Their continuous vibration causes other atoms to vibrate together, and a terrible disaster occurs. One atom after another vibrates faster and faster, combining vigorously, and everything changes. This "disaster" is fire. This is one way to describe "fire." This collision is constantly happening, never stopping. Once it starts, it continues to do so. The heat produced gives other atoms the ability to collide and produce more heat, causing more atoms to behave the same way. So this vigorous combination triggers a lot of vibration.

If I place those less energetic atoms over there, for example, if I place a cup of cold coffee next to a pile of burning wood. The atoms in the coffee will vibrate vigorously, that's the heat of the fire. Of course, there will be... See, this is what happens when you start thinking, you can't stop at all. You just want to know how it started. Why did the wood stay with the oxygen for so long without fire appearing before? Where did this heat come from? Actually, it comes from the tree. The substance of the tree is carbon. Where did that carbon come from? It comes from carbon dioxide in the air. People look at trees and think trees grow from the ground. Plants grow from the ground. But if you ask where the substance of the tree comes from, think carefully about where it comes from. Does the tree come from the air? Of course, trees do come from the air. Carbon dioxide in the air enters the tree, changes, kicks out oxygen atoms, forming oxygen and releasing it, leaving carbon atoms. Carbon and water form the substance of the tree. Water comes from the ground, and carbon atoms enter the tree from the air, right? It comes from the sky. Therefore, almost all trees come from the ground. Sorry, I misspoke, they all come from the air. Of course, a small amount comes from underground minerals, etc.

Of course, I told you oxygen atoms... Oxygen atoms and carbon atoms combine very tightly. So how does the tree cleverly absorb carbon dioxide? At this point, the carbon atoms and oxygen atoms are tightly bound, yet the tree can easily break them down? Ah! Life, is it some mysterious power of life? Wrong, it's the sun's rays. Sunlight shines in and separates the oxygen atoms and carbon atoms. Therefore, sunlight is needed for plants to grow. So the role of the sun is to continuously separate oxygen atoms and carbon atoms. Oxygen, as a kind of bad byproduct, is released into the air, leaving behind carbon atoms and water, which form the substance of the tree. Then we put the substance of the tree in the fireplace. The oxygen produced by the tree wants to combine with the carbon in the tree again. Once you heat it to trigger their combination, the whole process will continue. During their vigorous combination, intense thermal motion will occur. Thus, beautiful light and other things appear. It's as if nothing happened; you've turned oxygen and carbon back into carbon dioxide. But light and heat are produced, which are actually the light and heat of the sun radiating in. So when you light a piece of wood, it's like releasing the sun stored in the wood.

The next question is, why is the sun so active and so hot? I'll stop here and leave you with a question to imagine. Most elastic things, like steel bars or springs, are due to forces related to electricity pulling them back. When you bend something, you're pulling the atoms a little farther apart, so these atoms try to come back together. But a rubber band works differently. There are some long chain-like molecules, and some small molecules that are constantly vibrating and hitting these chain molecules. And the chain molecules are all twisted and funny shapes. When you straighten the rubber band, the chain molecules straighten out. But these chain molecules are constantly being hit from the sides. Other atoms try to twist them, making them contract. Therefore, the rubber band tries to contract. It contracts simply due to heat. So if you heat a rubber band, it will contract more. For example, if you hang a heavy object with a rubber band and then bring a lit match close to the rubber band, it's quite interesting to watch the heavy object rise as the rubber band is heated.

You can also prove this point in another way. To prove that it is indeed heat that drives the contraction of a rubber band. When you stretch a rubber band, it's like compressing the piston and internal gas downwards. If you stretch a rubber band, the stretched chain molecules hit other molecules, making them move faster, so the temperature rises. And when you contract the rubber band, the molecules lose some energy when they hit the chain molecules. It's like hitting something soft; it sinks in and "bang bang." Energy is lost. When you pull the piston out, the atoms hit it and their speed decreases, so the temperature drops. So when a gas expands, its temperature decreases.

The interesting thing is that all the phenomena you observe in this world, such as your gas compressing and heating up, expanding and cooling down, or water evaporating from a cup if it's not covered. All these phenomena can be understood using a simple atomic picture. Thinking this way is very interesting. I don't want to take this kind of thinking too seriously. I think we should imagine happily, without any worries. There won't be a teacher asking questions at the end, otherwise it's an annoying subject.

Different atoms want to be close to each other to varying degrees. For example, oxygen atoms in the air want to be close to carbon atoms. If they get too close, they combine vigorously. If they are not very close, they repel each other and separate. So they don't know they can combine. It's like a ball trying to climb a hill. There's a hole in front of it, into which it can fall, like a crater. A deep opening. The ball just circles around it and doesn't fall in. Because when the ball starts to climb the slope, it rolls back. But if you make it go fast enough to pass the critical point, it will fall into the hole. So if something like wood comes into contact with oxygen, and there are carbon atoms in the wood. The oxygen atoms come and hit the carbon atoms, but the temperature isn't high enough. The oxygen atoms run away again. Air always comes and goes, and nothing happens.

If you heat the oxygen atoms in some way to make them faster, to accelerate a few atoms at first, meaning to get them past the critical point. They get close enough to the carbon atoms, and then they combine vigorously. This will produce more vigorous vibrations, possibly hitting other atoms and making them move faster, so they can pass the critical point and hit other carbon atoms. Their continuous vibration causes other atoms to vibrate together, and a terrible disaster occurs. One atom after another vibrates faster and faster, combining vigorously, and everything changes. This "disaster" is fire. This is one way to describe "fire." This collision is constantly happening, never stopping. Once it starts, it continues to do so. The heat produced gives other atoms the ability to collide and produce more heat, causing more atoms to behave the same way. So this vigorous combination triggers a lot of vibration.

If I place those less energetic atoms over there, for example, if I place a cup of cold coffee next to a pile of burning wood. The atoms in the coffee will vibrate vigorously, that's the heat of the fire. Of course, there will be... See, this is what happens when you start thinking, you can't stop at all. You just want to know how it started. Why did the wood stay with the oxygen for so long without fire appearing before? Where did this heat come from? Actually, it comes from the tree. The substance of the tree is carbon. Where did that carbon come from? It comes from carbon dioxide in the air. People look at trees and think trees grow from the ground. Plants grow from the ground. But if you ask where the substance of the tree comes from, think carefully about where it comes from. Does the tree come from the air? Of course, trees do come from the air. Carbon dioxide in the air enters the tree, changes, kicks out oxygen atoms, forming oxygen and releasing it, leaving carbon atoms. Carbon and water form the substance of the tree. Water comes from the ground, and carbon atoms enter the tree from the air, right? It comes from the sky. Therefore, almost all trees come from the ground. Sorry, I misspoke, they all come from the air. Of course, a small amount comes from underground minerals, etc.

Of course, I told you oxygen atoms... Oxygen atoms and carbon atoms combine very tightly. So how does the tree cleverly absorb carbon dioxide? At this point, the carbon atoms and oxygen atoms are tightly bound, yet the tree can easily break them down? Ah! Life, is it some mysterious power of life? Wrong, it's the sun's rays. Sunlight shines in and separates the oxygen atoms and carbon atoms. Therefore, sunlight is needed for plants to grow. So the role of the sun is to continuously separate oxygen atoms and carbon atoms. Oxygen, as a kind of bad byproduct, is released into the air, leaving behind carbon atoms and water, which form the substance of the tree. Then we put the substance of the tree in the fireplace. The oxygen produced by the tree wants to combine with the carbon in the tree again. Once you heat it to trigger their combination, the whole process will continue. During their vigorous combination, intense thermal motion will occur. Thus, beautiful light and other things appear. It's as if nothing happened; you've turned oxygen and carbon back into carbon dioxide. But light and heat are produced, which are actually the light and heat of the sun radiating in. So when you light a piece of wood, it's like releasing the sun stored in the wood.

The next question is, why is the sun so active and so hot? I'll stop here and leave you with a question to imagine. Most elastic things, like steel bars or springs, are due to forces related to electricity pulling them back. When you bend something, you're pulling the atoms a little farther apart, so these atoms try to come back together. But a rubber band works differently. There are some long chain-like molecules, and some small molecules that are constantly vibrating and hitting these chain molecules. And the chain molecules are all twisted and funny shapes. When you straighten the rubber band, the chain molecules straighten out. But these chain molecules are constantly being hit from the sides. Other atoms try to twist them, making them contract. Therefore, the rubber band tries to contract. It contracts simply due to heat. So if you heat a rubber band, it will contract more. For example, if you hang a heavy object with a rubber band and then bring a lit match close to the rubber band, it's quite interesting to watch the heavy object rise as the rubber band is heated.

You can also prove this point in another way. To prove that it is indeed heat that drives the contraction of a rubber band. When you stretch a rubber band, it's like compressing the piston and internal gas downwards. If you stretch a rubber band, the stretched chain molecules hit other molecules, making them move faster, so the temperature rises. And when you contract the rubber band, the molecules lose some energy when they hit the chain molecules. It's like hitting something soft; it sinks in and "bang bang." Energy is lost. When you pull the piston out, the atoms hit it and their speed decreases, so the temperature drops. So when a gas expands, its temperature decreases.

The interesting thing is that all the phenomena you observe in this world, such as your gas compressing and heating up, expanding and cooling down, or water evaporating from a cup if it's not covered. All these phenomena can be understood using a simple atomic picture. Thinking this way is very interesting. I don't want to take this kind of thinking too seriously. I think we should imagine happily, without any worries. There won't be a teacher asking questions at the end, otherwise it's an annoying subject.

Different atoms want to be close to each other to varying degrees. For example, oxygen atoms in the air want to be close to carbon atoms. If they get too close, they combine vigorously. If they are not very close, they repel each other and separate. So they don't know they can combine. It's like a ball trying to climb a hill. There's a hole in front of it, into which it can fall, like a crater. A deep opening. The ball just circles around it and doesn't fall in. Because when the ball starts to climb the slope, it rolls back. But if you make it go fast enough to pass the critical point, it will fall into the hole. So if something like wood comes into contact with oxygen, and there are carbon atoms in the wood. The oxygen atoms come and hit the carbon atoms, but the temperature isn't high enough. The oxygen atoms run away again. Air always comes and goes, and nothing happens.

If you heat the oxygen atoms in some way to make them faster, to accelerate a few atoms at first, meaning to get them past the critical point. They get close enough to the carbon atoms, and then they combine vigorously. This will produce more vigorous vibrations, possibly hitting other atoms and making them move faster, so they can pass the critical point and hit other carbon atoms. Their continuous vibration causes other atoms to vibrate together, and a terrible disaster occurs. One atom after another vibrates faster and faster, combining vigorously, and everything changes. This "disaster" is fire. This is one way to describe "fire." This collision is constantly happening, never stopping. Once it starts, it continues to do so. The heat produced gives other atoms the ability to collide and produce more heat, causing more atoms to behave the same way. So this vigorous combination triggers a lot of vibration.

If I place those less energetic atoms over there, for example, if I place a cup of cold coffee next to a pile of burning wood. The atoms in the coffee will vibrate vigorously, that's the heat of the fire. Of course, there will be... See, this is what happens when you start thinking, you can't stop at all. You just want to know how it started. Why did the wood stay with the oxygen for so long without fire appearing before? Where did this heat come from? Actually, it comes from the tree. The substance of the tree is carbon. Where did that carbon come from? It comes from carbon dioxide in the air. People look at trees and think trees grow from the ground. Plants grow from the ground. But if you ask where the substance of the tree comes from, think carefully about where it comes from. Does the tree come from the air? Of course, trees do come from the air. Carbon dioxide in the air enters the tree, changes, kicks out oxygen atoms, forming oxygen and releasing it, leaving carbon atoms. Carbon and water form the substance of the tree. Water comes from the ground, and carbon atoms enter the tree from the air, right? It comes from the sky. Therefore, almost all trees come from the ground. Sorry, I misspoke, they all come from the air. Of course, a small amount comes from underground minerals, etc.

Of course, I told you oxygen atoms... Oxygen atoms and carbon atoms combine very tightly. So how does the tree cleverly absorb carbon dioxide? At this point, the carbon atoms and oxygen atoms are tightly bound, yet the tree can easily break them down? Ah! Life, is it some mysterious power of life? Wrong, it's the sun's rays. Sunlight shines in and separates the oxygen atoms and carbon atoms. Therefore, sunlight is needed for plants to grow. So the role of the sun is to continuously separate oxygen atoms and carbon atoms. Oxygen, as a kind of bad byproduct, is released into the air, leaving behind carbon atoms and water, which form the substance of the tree. Then we put the substance of the tree in the fireplace. The oxygen produced by the tree wants to combine with the carbon in the tree again. Once you heat it to trigger their combination, the whole process will continue. During their vigorous combination, intense thermal motion will occur. Thus, beautiful light and other things appear. It's as if nothing happened; you've turned oxygen and carbon back into carbon dioxide. But light and heat are produced, which are actually the light and heat of the sun radiating in. So when you light a piece of wood, it's like releasing the sun stored in the wood.

The next question is, why is the sun so active and so hot? I'll stop here and leave you with a question to imagine. Most elastic things, like steel bars or springs, are due to forces related to electricity pulling them back. When you bend something, you're pulling the atoms a little farther apart, so these atoms try to come back together. But a rubber band works differently. There are some long chain-like molecules, and some small molecules that are constantly vibrating and hitting these chain molecules. And the chain molecules are all twisted and funny shapes. When you straighten the rubber band, the chain molecules straighten out. But these chain molecules are constantly being hit from the sides. Other atoms try to twist them, making them contract. Therefore, the rubber band tries to contract. It contracts simply due to heat. So if you heat a rubber band, it will contract more. For example, if you hang a heavy object with a rubber band and then bring a lit match close to the rubber band, it's quite interesting to watch the heavy object rise as the rubber band is heated.

You can also prove this point in another way. To prove that it is indeed heat that drives the contraction of a rubber band. When you stretch a rubber band, it's like compressing the piston and internal gas downwards. If you stretch a rubber band, the stretched chain molecules hit other molecules, making them move faster, so the temperature rises. And when you contract the rubber band, the molecules lose some energy when they hit the chain molecules. It's like hitting something soft; it sinks in and "bang bang." Energy is lost. When you pull the piston out, the atoms hit it and their speed decreases, so the temperature drops. So when a gas expands, its temperature decreases.

The interesting thing is that all the phenomena you observe in this world, such as your gas compressing and heating up, expanding and cooling down, or water evaporating from a cup if it's not covered. All these phenomena can be understood using a simple atomic picture. Thinking this way is very interesting. I don't want to take this kind of thinking too seriously. I think we should imagine happily, without any worries. There won't be a teacher asking questions at the end, otherwise it's an annoying subject.

Different atoms want to be close to each other to varying degrees. For example, oxygen atoms in the air want to be close to carbon atoms. If they get too close, they combine vigorously. If they are not very close, they repel each other and separate. So they don't know they can combine. It's like a ball trying to climb a hill. There's a hole in front of it, into which it can fall, like a crater. A deep opening. The ball just circles around it and doesn't fall in. Because when the ball starts to climb the slope, it rolls back. But if you make it go fast enough to pass the critical point, it will fall into the hole. So if something like wood comes into contact with oxygen, and there are carbon atoms in the wood. The oxygen atoms come and hit the carbon atoms, but the temperature isn't high enough. The oxygen atoms run away again. Air always comes and goes, and nothing happens.

If you heat the oxygen atoms in some way to make them faster, to accelerate a few atoms at first, meaning to get them past the critical point. They get close enough to the carbon atoms, and then they combine vigorously. This will produce more vigorous vibrations, possibly hitting other atoms and making them move faster, so they can pass the critical point and hit other carbon atoms. Their continuous vibration causes other atoms to vibrate together, and a terrible disaster occurs. One atom after another vibrates faster and faster, combining vigorously, and everything changes. This "disaster" is fire. This is one way to describe "fire." This collision is constantly happening, never stopping. Once it starts, it continues to do so. The heat produced gives other atoms the ability to collide and produce more heat, causing more atoms to behave the same way. So this vigorous combination triggers a lot of vibration.

If I place those less energetic atoms over there, for example, if I place a cup of cold coffee next to a pile of burning wood. The atoms in the coffee will vibrate vigorously, that's the heat of the fire. Of course, there will be... See, this is what happens when you start thinking, you can't stop at all. You just want to know how it started. Why did the wood stay with the oxygen for so long without fire appearing before? Where did this heat come from? Actually, it comes from the tree. The substance of the tree is carbon. Where did that carbon come from? It comes from carbon dioxide in the air. People look at trees and think trees grow from the ground. Plants grow from the ground. But if you ask where the substance of the tree comes from, think carefully about where it comes from. Does the tree come from the air? Of course, trees do come from the air. Carbon dioxide in the air enters the tree, changes, kicks out oxygen atoms, forming oxygen and releasing it, leaving carbon atoms. Carbon and water form the substance of the tree. Water comes from the ground, and carbon atoms enter the tree from the air, right? It comes from the sky. Therefore, almost all trees come from the ground. Sorry, I misspoke, they all come from the air. Of course, a small amount comes from underground minerals, etc.

Of course, I told you oxygen atoms... Oxygen atoms and carbon atoms combine very tightly. So how does the tree cleverly absorb carbon dioxide? At this point, the carbon atoms and oxygen atoms are tightly bound, yet the tree can easily break them down? Ah! Life, is it some mysterious power of life? Wrong, it's the sun's rays. Sunlight shines in and separates the oxygen atoms and carbon atoms. Therefore, sunlight is needed for plants to grow. So the role of the sun is to continuously separate oxygen atoms and carbon atoms. Oxygen, as a kind of bad byproduct, is released into the air, leaving behind carbon atoms and water, which form the substance of the tree. Then we put the substance of the tree in the fireplace. The oxygen produced by the tree wants to combine with the carbon in the tree again. Once you heat it to trigger their combination, the whole process will continue. During their vigorous combination, intense thermal motion will occur. Thus, beautiful light and other things appear. It's as if nothing happened; you've turned oxygen and carbon back into carbon dioxide. But light and heat are produced, which are actually the light and heat of the sun radiating in. So when you light a piece of wood, it's like releasing the sun stored in the wood.

The next question is, why is the sun so active and so hot? I'll stop here and leave you with a question to imagine. Most elastic things, like steel bars or springs, are due to forces related to electricity pulling them back. When you bend something, you're pulling the atoms a little farther apart, so these atoms try to come back together. But a rubber band works differently. There are some long chain-like molecules, and some small molecules that are constantly vibrating and hitting these chain molecules. And the chain molecules are all twisted and funny shapes. When you straighten the rubber band, the chain molecules straighten out. But these chain molecules are constantly being hit from the sides. Other atoms try to twist them, making them contract. Therefore, the rubber band tries to contract. It contracts simply due to heat. So if you heat a rubber band, it will contract more. For example, if you hang a heavy object with a rubber band and then bring a lit match close to the rubber band, it's quite interesting to watch the heavy object rise as the rubber band is heated.

You can also prove this point in another way. To prove that it is indeed heat that drives the contraction of a rubber band. When you stretch a rubber band, it's like compressing the piston and internal gas downwards. If you stretch a rubber band, the stretched chain molecules hit other molecules, making them move faster, so the temperature rises. And when you contract the rubber band, the molecules lose some energy when they hit the chain molecules. It's like hitting something soft; it sinks in and "bang bang." Energy is lost. When you pull the piston out, the atoms hit it and their speed decreases, so the temperature drops. So when a gas expands, its temperature decreases.

The interesting thing is that all the phenomena you observe in this world, such as your gas compressing and heating up, expanding and cooling down, or water evaporating from a cup if it's not covered. All these phenomena can be understood using a simple atomic picture. Thinking this way is very interesting. I don't want to take this kind of thinking too seriously. I think we should imagine happily, without any worries. There won't be a teacher asking questions at the end, otherwise it's an annoying subject.

Different atoms want to be close to each other to varying degrees. For example, oxygen atoms in the air want to be close to carbon atoms. If they get too close, they combine vigorously. If they are not very close, they repel each other and separate. So they don't know they can combine. It's like a ball trying to climb a hill. There's a hole in front of it, into which it can fall, like a crater. A deep opening. The ball just circles around it and doesn't fall in. Because when the ball starts to climb the slope, it rolls back. But if you make it go fast enough to pass the critical point, it will fall into the hole. So if something like wood comes into contact with oxygen, and there are carbon atoms in the wood. The oxygen atoms come and hit the carbon atoms, but the temperature isn't high enough. The oxygen atoms run away again. Air always comes and goes, and nothing happens.

If you heat the oxygen atoms in some way to make them faster, to accelerate a few atoms at first, meaning to get them past the critical point. They get close enough to the carbon atoms, and then they combine vigorously. This will produce more vigorous vibrations, possibly hitting other atoms and making them move faster, so they can pass the critical point and hit other carbon atoms. Their continuous vibration causes other atoms to vibrate together, and a terrible disaster occurs. One atom after another vibrates faster and faster, combining vigorously, and everything changes. This "disaster" is fire. This is one way to describe "fire." This collision is constantly happening, never stopping. Once it starts, it continues to do so. The heat produced gives other atoms the ability to collide and produce more heat, causing more atoms to behave the same way. So this vigorous combination triggers a lot of vibration.

If I place those less energetic atoms over there, for example, if I place a cup of cold coffee next to a pile of burning wood. The atoms in the coffee will vibrate vigorously, that's the heat of the fire. Of course, there will be... See, this is what happens when you start thinking, you can't stop at all. You just want to know how it started. Why did the wood stay with the oxygen for so long without fire appearing before? Where did this heat come from? Actually, it comes from the tree. The substance of the tree is carbon. Where did that carbon come from? It comes from carbon dioxide in the air. People look at trees and think trees grow from the ground. Plants grow from the ground. But if you ask where the substance of the tree comes from, think carefully about where it comes from. Does the tree come from the air? Of course, trees do come from the air. Carbon dioxide in the air enters the tree, changes, kicks out oxygen atoms, forming oxygen and releasing it, leaving carbon atoms. Carbon and water form the substance of the tree. Water comes from the ground, and carbon atoms enter the tree from the air, right? It comes from the sky. Therefore, almost all trees come from the ground. Sorry, I misspoke, they all come from the air. Of course, a small amount comes from underground minerals, etc.

Of course, I told you oxygen atoms... Oxygen atoms and carbon atoms combine very tightly. So how does the tree cleverly absorb carbon dioxide? At this point, the carbon atoms and oxygen atoms are tightly bound, yet the tree can easily break them down? Ah! Life, is it some mysterious power of life? Wrong, it's the sun's rays. Sunlight shines in and separates the oxygen atoms and carbon atoms. Therefore, sunlight is needed for plants to grow. So the role of the sun is to continuously separate oxygen atoms and carbon atoms. Oxygen, as a kind of bad byproduct, is released into the air, leaving behind carbon atoms and water, which form the substance of the tree. Then we put the substance of the tree in the fireplace. The oxygen produced by the tree wants to combine with the carbon in the tree again. Once you heat it to trigger their combination, the whole process will continue. During their vigorous combination, intense thermal motion will occur. Thus, beautiful light and other things appear. It's as if nothing happened; you've turned oxygen and carbon back into carbon dioxide. But light and heat are produced, which are actually the light and heat of the sun radiating in. So when you light a piece of wood, it's like releasing the sun stored in the wood.

The next question is, why is the sun so active and so hot? I'll stop here and leave you with a question to imagine. Most elastic things, like steel bars or springs, are due to forces related to electricity pulling them back. When you bend something, you're pulling the atoms a little farther apart, so these atoms try to come back together. But a rubber band works differently. There are some long chain-like molecules, and some small molecules that are constantly vibrating and hitting these chain molecules. And the chain molecules are all twisted and funny shapes. When you straighten the rubber band, the chain molecules straighten out. But these chain molecules are constantly being hit from the sides. Other atoms try to twist them, making them contract. Therefore, the rubber band tries to contract. It contracts simply due to heat. So if you heat a rubber band, it will contract more. For example, if you hang a heavy object with a rubber band and then bring a lit match close to the rubber band, it's quite interesting to watch the heavy object rise as the rubber band is heated.

You can also prove this point in another way. To prove that it is indeed heat that drives the contraction of a rubber band. When you stretch a rubber band, it's like compressing the piston and internal gas downwards. If you stretch a rubber band, the stretched chain molecules hit other molecules, making them move faster, so the temperature rises. And when you contract the rubber band, the molecules lose some energy when they hit the chain molecules. It's like hitting something soft; it sinks in and "bang bang." Energy is lost. When you pull the piston out, the atoms hit it and their speed decreases, so the temperature drops. So when a gas expands, its temperature decreases.

The interesting thing is that all the phenomena you observe in this world, such as your gas compressing and heating up, expanding and cooling down, or water evaporating from a cup if it's not covered. All these phenomena can be understood using a simple atomic picture. Thinking this way is very interesting. I don't want to take this kind of thinking too seriously. I think we should imagine happily, without any worries. There won't be a teacher asking questions at the end, otherwise it's an annoying subject.

Different atoms want to be close to each other to varying degrees. For example, oxygen atoms in the air want to be close to carbon atoms. If they get too close, they combine vigorously. If they are not very close, they repel each other and separate. So they don't know they can combine. It's like a ball trying to climb a hill. There's a hole in front of it, into which it can fall, like a crater. A deep opening. The ball just circles around it and doesn't fall in. Because when the ball starts to climb the slope, it rolls back. But if you make it go fast enough to pass the critical point, it will fall into the hole. So if something like wood comes into contact with oxygen, and there are carbon atoms in the wood. The oxygen atoms come and hit the carbon atoms, but the temperature isn't high enough. The oxygen atoms run away again. Air always comes and goes, and nothing happens.

If you heat the oxygen atoms in some way to make them faster, to accelerate a few atoms at first, meaning to get them past the critical point. They get close enough to the carbon atoms, and then they combine vigorously. This will produce more vigorous vibrations, possibly hitting other atoms and making them move faster, so they can pass the critical point and hit other carbon atoms. Their continuous vibration causes other atoms to vibrate together, and a terrible disaster occurs. One atom after another vibrates faster and faster, combining vigorously, and everything changes. This "disaster" is fire. This is one way to describe "fire." This collision is constantly happening, never stopping. Once it starts, it continues to do so. The heat produced gives other atoms the ability to collide and produce more heat, causing more atoms to behave the same way. So this vigorous combination triggers a lot of vibration.

If I place those less energetic atoms over there, for example, if I place a cup of cold coffee next to a pile of burning wood. The atoms in the coffee will vibrate vigorously, that's the heat of the fire. Of course, there will be... See, this is what happens when you start thinking, you can't stop at all. You just want to know how it started. Why did the wood stay with the oxygen for so long without fire appearing before? Where did this heat come from? Actually, it comes from the tree. The substance of the tree is carbon. Where did that carbon come from? It comes from carbon dioxide in the air. People look at trees and think trees grow from the ground. Plants grow from the ground. But if you ask where the substance of the tree comes from, think carefully about where it comes from. Does the tree come from the air? Of course, trees do come from the air. Carbon dioxide in the air enters the tree, changes, kicks out oxygen atoms, forming oxygen and releasing it, leaving carbon atoms. Carbon and water form the substance of the tree. Water comes from the ground, and carbon atoms enter the tree from the air, right? It comes from the sky. Therefore, almost all trees come from the ground. Sorry, I misspoke, they all come from the air. Of course, a small amount comes from underground minerals, etc.

Of course, I told you oxygen atoms... Oxygen atoms and carbon atoms combine very tightly. So how does the tree cleverly absorb carbon dioxide? At this point, the carbon atoms and oxygen atoms are tightly bound, yet the tree can easily break them down? Ah! Life, is it some mysterious power of life? Wrong, it's the sun's rays. Sunlight shines in and separates the oxygen atoms and carbon atoms. Therefore, sunlight is needed for plants to grow. So the role of the sun is to continuously separate oxygen atoms and carbon atoms. Oxygen, as a kind of bad byproduct, is released into the air, leaving behind carbon atoms and water, which form the substance of the tree. Then we put the substance of the tree in the fireplace. The oxygen produced by the tree wants to combine with the carbon in the tree again. Once you heat it to trigger their combination, the whole process will continue. During their vigorous combination, intense thermal motion will occur. Thus, beautiful light and other things appear. It's as if nothing happened; you've turned oxygen and carbon back into carbon dioxide. But light and heat are produced, which are actually the light and heat of the sun radiating in. So when you light a piece of wood, it's like releasing the sun stored in the wood.

The next question is, why is the sun so active and so hot? I'll stop here and leave you with a question to imagine. Most elastic things, like steel bars or springs, are due to forces related to electricity pulling them back. When you bend something, you're pulling the atoms a little farther apart, so these atoms try to come back together. But a rubber band works differently. There are some long chain-like molecules, and some small molecules that are constantly vibrating and hitting these chain molecules. And the chain molecules are all twisted and funny shapes. When you straighten the rubber band, the chain molecules straighten out. But these chain molecules are constantly being hit from the sides. Other atoms try to twist them, making them contract. Therefore, the rubber band tries to contract. It contracts simply due to heat. So if you heat a rubber band, it will contract more. For example, if you hang a heavy object with a rubber band and then bring a lit match close to the rubber band, it's quite interesting to watch the heavy object rise as the rubber band is heated.

You can also prove this point in another way. To prove that it is indeed heat that drives the contraction of a rubber band. When you stretch a rubber band, it's like compressing the piston and internal gas downwards. If you stretch a rubber band, the stretched chain molecules hit other molecules, making them move faster, so the temperature rises. And when you contract the rubber band, the molecules lose some energy when they hit the chain molecules. It's like hitting something soft; it sinks in and "bang bang." Energy is lost. When you pull the piston out, the atoms hit it and their speed decreases, so the temperature drops. So when a gas expands, its temperature decreases.

The interesting thing is that all the phenomena you observe in this world, such as your gas compressing and heating up, expanding and cooling down, or water evaporating from a cup if it's not covered. All these phenomena can be understood using a simple atomic picture. Thinking this way is very interesting. I don't want to take this kind of thinking too seriously. I think we should imagine happily, without any worries. There won't be a teacher asking questions at the end, otherwise it's an annoying subject.

Different atoms want to be close to each other to varying degrees. For example, oxygen atoms in the air want to be close to carbon atoms. If they get too close, they combine vigorously. If they are not very close, they repel each other and separate. So they don't know they can combine. It's like a ball trying to climb a hill. There's a hole in front of it, into which it can fall, like a crater. A deep opening. The ball just circles around it and doesn't fall in. Because when the ball starts to climb the slope, it rolls back. But if you make it go fast enough to pass the critical point, it will fall into the hole. So if something like wood comes into contact with oxygen, and there are carbon atoms in the wood. The oxygen atoms come and hit the carbon atoms, but the temperature isn't high enough. The oxygen atoms run away again. Air always comes and goes, and nothing happens.

If you heat the oxygen atoms in some way to make them faster, to accelerate a few atoms at first, meaning to get them past the critical point. They get close enough to the carbon atoms, and then they combine vigorously. This will produce more vigorous vibrations, possibly hitting other atoms and making them move faster, so they can pass the critical point and hit other carbon atoms. Their continuous vibration causes other atoms to vibrate together, and a terrible disaster occurs. One atom after another vibrates faster and faster, combining vigorously, and everything changes. This "disaster" is fire. This is one way to describe "fire." This collision is constantly happening, never stopping. Once it starts, it continues to do so. The heat produced gives other atoms the ability to collide and produce more heat, causing more atoms to behave the same way. So this vigorous combination triggers a lot of vibration.

If I place those less energetic atoms over there, for example, if I place a cup of cold coffee next to a pile of burning wood. The atoms in the coffee will vibrate vigorously, that's the heat of the fire. Of course, there will be... See, this is what happens when you start thinking, you can't stop at all. You just want to know how it started. Why did the wood stay with the oxygen for so long without fire appearing before? Where did this heat come from? Actually, it comes from the tree. The substance of the tree is carbon. Where did that carbon come from? It comes from carbon dioxide in the air. People look at trees and think trees grow from the ground. Plants grow from the ground. But if you ask where the substance of the tree comes from, think carefully about where it comes from. Does the tree come from the air? Of course, trees do come from the air. Carbon dioxide in the air enters the tree, changes, kicks out oxygen atoms, forming oxygen and releasing it, leaving carbon atoms. Carbon and water form the substance of the tree. Water comes from the ground, and carbon atoms enter the tree from the air, right? It comes from the sky. Therefore, almost all trees come from the ground. Sorry, I misspoke, they all come from the air. Of course, a small amount comes from underground minerals, etc.

Of course, I told you oxygen atoms... Oxygen atoms and carbon atoms combine very tightly. So how does the tree cleverly absorb carbon dioxide? At this point, the carbon atoms and oxygen atoms are tightly bound, yet the tree can easily break them down? Ah! Life, is it some mysterious power of life? Wrong, it's the sun's rays. Sunlight shines in and separates the oxygen atoms and carbon atoms. Therefore, sunlight is needed for plants to grow. So the role of the sun is to continuously separate oxygen atoms and carbon atoms. Oxygen, as a kind of bad byproduct, is released into the air, leaving behind carbon atoms and water, which form the substance of the tree. Then we put the substance of the tree in the fireplace. The oxygen produced by the tree wants to combine with the carbon in the tree again. Once you heat it to trigger their combination, the whole process will continue. During their vigorous combination, intense thermal motion will occur. Thus, beautiful light and other things appear. It's as if nothing happened; you've turned oxygen and carbon back into carbon dioxide. But light and heat are produced, which are actually the light and heat of the sun radiating in. So when you light a piece of wood, it's like releasing the sun stored in the wood.

The next question is, why is the sun so active and so hot? I'll stop here and leave you with a question to imagine. Most elastic things, like steel bars or springs, are due to forces related to electricity pulling them back. When you bend something, you're pulling the atoms a little farther apart, so these atoms try to come back together. But a rubber band works differently. There are some long chain-like molecules, and some small molecules that are constantly vibrating and hitting these chain molecules. And the chain molecules are all twisted and funny shapes. When you straighten the rubber band, the chain molecules straighten out. But these chain molecules are constantly being hit from the sides. Other atoms try to twist them, making them contract. Therefore, the rubber band tries to contract. It contracts simply due to heat. So if you heat a rubber band, it will contract more. For example, if you hang a heavy object with a rubber band and then bring a lit match close to the rubber band, it's quite interesting to watch the heavy object rise as the rubber band is heated.

You can also prove this point in another way. To prove that it is indeed heat that drives the contraction of a rubber band. When you stretch a rubber band, it's like compressing the piston and internal gas downwards. If you stretch a rubber band, the stretched chain molecules hit other molecules, making them move faster, so the temperature rises. And when you contract the rubber band, the molecules lose some energy when they hit the chain molecules. It's like hitting something soft; it sinks in and "bang bang." Energy is lost. When you pull the piston out, the atoms hit it and their speed decreases, so the temperature drops. So when a gas expands, its temperature decreases.

The interesting thing is that all the phenomena you observe in this world, such as your gas compressing and heating up, expanding and cooling down, or water evaporating from a cup if it's not covered. All these phenomena can be understood using a simple atomic picture. Thinking this way is very interesting. I don't want to take this kind of thinking too seriously. I think we should imagine happily, without any worries. There won't be a teacher asking questions at the end, otherwise it's an annoying subject.

Different atoms want to be close to each other to varying degrees. For example, oxygen atoms in the air want to be close to carbon atoms. If they get too close, they combine vigorously. If they are not very close, they repel each other and separate. So they don't know they can combine. It's like a ball trying to climb a hill. There's a hole in front of it, into which it can fall, like a crater. A deep opening. The ball just circles around it and doesn't fall in. Because when the ball starts to climb the slope, it rolls back. But if you make it go fast enough to pass the critical point, it will fall into the hole. So if something like wood comes into contact with oxygen, and there are carbon atoms in the wood. The oxygen atoms come and hit the carbon atoms, but the temperature isn't high enough. The oxygen atoms run away again. Air always comes and goes, and nothing happens.

If you heat the oxygen atoms in some way to make them faster, to accelerate a few atoms at first, meaning to get them past the critical point. They get close enough to the carbon atoms, and then they combine vigorously. This will produce more vigorous vibrations, possibly hitting other atoms and making them move faster, so they can pass the critical point and hit other carbon atoms. Their continuous vibration causes other atoms to vibrate together, and a terrible disaster occurs. One atom after another vibrates faster and faster, combining vigorously, and everything changes. This "dis