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800 kW power is supplied to a motor of 7...

800 kW power is supplied to a motor of 70% efficiency. This motor is in turn connected to a crane, whose efficiency is also 70%. If this crane lifts a 20 ton rock, its velocity is

A

`2ms^(-1)`

B

`0.2ms^(-1)`

C

`20ms^(-1)`

D

`10ms^(-1)`

Text Solution

Verified by Experts

The correct Answer is:
A
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