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An elevator is moving upward with an acc...

An elevator is moving upward with an acceleration a it has velocity v when a man inside the elevator lifts a body of mass m through a height h ( in time t). The average power developed by the man is

A

`(m(g+a)h)/(t)`

B

`m(g+a)(v+1/2 a t)`

C

`(mgh)/(t)`

D

`mg(v+1/2 at)`

Text Solution

Verified by Experts

The correct Answer is:
A
The power developed by the man `=` power required in the refrence frame of the man `="Force"xx"velocity"=m(g+a).(h//t)`
Hence (A) is correct
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