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प्रश्न
.A man raises a box of mass 50kg to a height of 2m in 20s, while another man raises the same box to the same height in 50s. Compare:
(i) the work done, and
(ii) the power developed by them.
उत्तर
(i) Work done to raise the block of mass 50kg is same for both.
(ii) Power= Work done/time. As the time taken by the first man is less therefore power developed is more.
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