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A coin is dropped in a lift. It takes ti...

A coin is dropped in a lift. It takes time `t_(1)` to reach the floor when lift is stationary. It takes time `t_(2)` when lift is moving up with constant acceleration. Then

A

`t_(1) = t_(2)`

B

`t_(1) gt t_(2)`

C

`t_(2) gt t_(1)`

D

`t_(1) gt gt t_(2)`

Text Solution

Verified by Experts

The correct Answer is:
B

(b) Time `t_(1)` for stationary lift `=sqrt((2h)/(g))`
When lift is moving up with constant acceleration , then `t_(2)=sqrt((2h)/(g+a))`[Relative acceleration =(g+a)]
`therefore t_(1)gt t_(2)`
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