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An elevator (a lift ) is moving up at th...

An elevator (a lift ) is moving up at the speed of 2 m/s in a shaft . At the instant the elevator is 20 m from the top , a ball is dropped from the top of the shaft . The ball rebounds elastically from the elevators roof . To what height can it rise relative to the top of the shaft ?

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The correct Answer is:
`8.34` m
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NN GHOSH-LAWS OF MOTION, FREE BODY DIAGRAM-Exercise (A)
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