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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 does the same in 15 s. Compare the work done.
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Solution
The work done by two persons, A and B, does not depend upon time. Therefore, both will do the same amount of work. Thus, we arrive to the conclusion that
Work done by A = Force × height = mgh
Work done by B = Force × height = mgh
∴ mgh = mgh
`"Work done by A"/"Work done by B" = 1/1` = 1 : 1
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