Amar, Javed, and Rita were riding in a bus that was moving with a high velocity on a highway when a bug hit the windshield and its dead body got stuck on the windscreen. Amar and Javed began discussing the situation. Amar suggested that the change in momentum of the bug is much greater than that of the bus. After all, argued Amar, there was no noticeable change in the velocity of the bus compared to the obvious change in the velocity of the bug. Javed opined that since the bus was moving with a larger velocity, so it exerted a larger force on the bug, as a result of which it died. Rita disagreed entirely, arguing that both the bug and bus experienced the same force and a change in their momentum. Who do you agree with? Support your answer.

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(D) According to Newton's third law of motion, for every action, there is an equal and opposite reaction. Therefore, the force exerted by the bus on the bug is equal in magnitude to the force exerted by the bug on the bus.
Since the force $(F)$ and the time of impact $(t)$ are the same for both, the change in momentum $(\Delta p = F \times t)$ is also the same for both the bug and the bus.
However, because the mass of the bus is much larger than the mass of the bug, the change in velocity $(\Delta v = \Delta p / m)$ for the bus is negligible, whereas the change in velocity for the bug is very large.
Consequently, the bug experiences a much higher acceleration, leading to its death. Rita is correct in stating that both experience the same force and the same change in momentum.

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