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The ball is dropped from a bridge 122.5...

The ball is dropped from a bridge ` 122.5 m` above a river, After the ball has been falling for 2 s, a second ball is thrown straight down after it. What must its initial velocity be so that both hit the water at the same time ?

A

49 m/sec

B

55.5 m/sec

C

26.1 m/sec

D

9.8 m/sec

Text Solution

Verified by Experts

The correct Answer is:
c
122.5 = ` 0 + (1//2) 9.8 t^(2), t = 5` sec, For the second ball `122.5 = ut + 1//2gt^(2), t = 5-2=3`
sec, solving `u = 26.1 ms^(-1)`
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