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Question
It takes 20 s for a person A of mass 50 kg to climb up the stairs, while another person B of same mass does the same in 15 s. Compare the power developed by the persons A and B.
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Solution
Power developed by the persons A and B is
`p_1/p_2 = ((mgh)/t_1)/((mgh)/t_2) = t_2/t_1 = 15/20 = 3:4`
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