Transcription
[Music] What happened? What happened? The big car slid a little, but the smaller one took off. Why? That's due to Newton's second law of motion, a topic we will explore in today's episode. So let's zoom in.
Remember what we learned in our previous video about Newton's first law of motion? Let's do a quick revision. It said an object at rest remains at rest, or if in motion remains in motion at a constant velocity unless acted upon by an unbalanced force.
I know what you are thinking: Why does the force have to be unbalanced? Well, the reason is that when an object is at rest or in motion, there are usually two forces acting on it: the normal force and the gravitational force. These forces are balanced, so the object stays in its current state. But when a new external force, like a push or pull, is applied, it creates an unbalanced force. This unbalanced force disturbs the object's initial state, causing it to accelerate, which means speeding up, slowing down, or changing direction.
Now, the vital question is: What's this net unbalanced force that influences the acceleration of an object? Well, according to Newton's second law of motion, acceleration depends on two major factors: the net force acting on the object and the object's mass.
Let's try to understand this with examples. Imagine you have a chair on a smooth wooden floor. You decide to push the chair gently with a small force of 5 Newtons. The chair starts to move slowly across the floor. Now you decide to push the chair harder with a larger force of 10 Newtons. What do you think happens to the acceleration of the chair? Exactly, the chair moves faster when you apply the larger force. This is because the acceleration is greater when the force is greater. So we can conclude: the more force you apply, the more the acceleration. Conversely, if you apply less force, the acceleration will be less. This demonstrates that acceleration is directly proportional to the net force applied.
Now let's look at how mass influences acceleration by comparing two objects. Imagine you have two boxes; one weighs 2 kg and the other weighs 4 kg. You apply an equal force of 10 Newtons to each box. Which do you think will accelerate more? Yes, you guessed it right: the 2 kg box will accelerate more because it has a lesser mass. This is because, for the same force, a lighter object will always accelerate faster than a heavier one. So we can conclude: the lesser the mass, the greater the acceleration, and the more the mass, the lesser the acceleration. Hence, we can say that acceleration depends inversely on the object's mass.
So to conclude, acceleration is directly proportional to the net force applied to an object and inversely proportional to the mass of the object; or, as some people like to write it: Fnet = m x a, which means that the net force is the product of mass and acceleration. Easy, isn't it, my friends?
Trivia time: Did you know the unit of force is called a newton, named after Isaac Newton himself? One newton is roughly the amount of force you need to lift an apple.
It's sketching time! Today's sketch of the day goes to Trishaan Chakraverti. Hope you learned important physics today. Until next time, it's me, Dr. Binox, zooming out. How's that possible? It's cartoon B. Never mind.