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Two girls each of weigth 400N, climb up ...

Two girls each of weigth 400N, climb up a rope through a height of 8m. We name one of the girls A and the other B. Girl A takes 20s while B takes 50s to accomplish this task. What is the power expneded by each girl.

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The correct Answer is:
A, D
Power expended by girl, A, i.e., `P_1(mgh)/(t_1) = ((400N)(8m))/(20s) =160W`
Power expended by girl B, i.e., `P_2 = (mgh)/(t_2) = ((400N)(8m))/(50s) = 64W`
`("weight of each girl", mg = 400N)`
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