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One man takes 1 minute to raise a box to...

One man takes 1 minute to raise a box to a height of 1 metre and another man takes `1/2` minute to do so. The energy of the two is 

A

different

B

same

C

energy of the first is more

D

energy of the second is more

Text Solution

Verified by Experts

The correct Answer is:
B
Energy required = mgh. In both cases, h is the same. Hence , energy given by the both is same. [It is worth nothing here that powers of two men will be different as power is the energy expense per unit time and times are different here. ]
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Knowledge Check

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