Akhtar, Kiran, and Rahul were riding in a motorcar that was moving with a high velocity on an expressway when an insect hit the windshield and got stuck on the windscreen. Akhtar and Kiran started pondering over the situation. Kiran suggested that the insect suffered a greater change in momentum as compared to the change in momentum of the motorcar (because the change in the velocity of the insect was much more than that of the motorcar). Akhtar said that since the motorcar was moving with a larger velocity, it exerted a larger force on the insect. And as a result, the insect died. Rahul while putting an entirely new explanation said that both the motorcar and the insect experienced the same force and a change in their momentum. Comment on these suggestions.

Here, let's see the statements of three persons:

Akhtar: The motorcar was moving with a larger velocity, it exerted a larger force on the insect. And as a result, the insect died.

If the car was moving slowly, the insect may have experienced less force and may have not died. Since the motorcar moving with a larger velocity exerted a larger force.

So, Aktar's suggestion is correct.

Kiran: The insect suffered a greater change in momentum as compared to the change in momentum of the motorcar $(because\ the\ change\ in\ the\ velocity\ of\ the\ insect\ was\ much\ more\ than\ that\ of\ the\ motorcar)$. So, the insect died.

We know the law of conservation of momentum,

Total momentum before collision$=$Total momentum after the collision

As the car is heavy and moving at a greater speed, and when it hits the insect, the insect experiences a larger change in momentum.

So, Kiran's suggestion is correct.

Rahul: Both the motorcar and the insect experienced the same force and a change in their momentum.

Rahul's suggestion is partially correct. It is as:

• Both the motorcar and the insect experienced the same force. it is according to the third law of motion that states that for every action, there is a reaction.
• But the change in the momentum of both the motorcar and the insect is not the same at all.

So, Rahul's suggestion is only partially correct.

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