Question

What happens when a very light body is motion colloids head on with a heavy stationary body in an elastic collision?

Answer 1

In such a case where m << M
The velocity of the heavier object does not get affected or is slightly affected. (V`=V)
Whereas, the lighter object gains a velocity in the opposite direction of it's initial motion or in the direction of the heavier object and (v`= 2V-v)

Hope it helps.

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