Question

A ball a is thrown vertically upwards with velocity u and at the same instant another ball is released from height h the velocity relative of a with b

Answer 1

Explanation:

velocity of ball A is at any t  vA=u−gt

velocity of ball B is released from height h at any time t vB=−gt

speed of A relative to B is vA/B=vA−vB=u−gt−(−gt)=u

Hence the correct answer is B

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