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During vertical motion under gravity a b...

During vertical motion under gravity a body passes through a point at 4s and 12 s in upwards and downwards journeys. The speed at this point is

A

g

B

2g

C

3g

D

4g

Text Solution

Verified by Experts

The correct Answer is:
D
Time for (rise CB + fall BC) is 8 s.
`therefore` Time for rise CB = Time for fall BC = 4s
Speed at C = speed gained in 4s
`v = u + g t = 0 + g xx 4 = 4g`

The body after projection reaches the highest point B where the speed becomes zero. Then, it falls under gravity.
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