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Question
A water pump raises 50 kg of water through a height of 25 m in 5s. Calculate the power supplied by the pump (Take: g = 10 N kg−1).
Solution
Given m = 50 kg, g = 10N kg−1, d = 25 m, t = 5s.
Force of gravity F = mg
= 50 × 10
= 500 N
Work done W = F × d
= 500 × 25
= 12,500 J
Power P =`"W"/"t" = (12,500)/5=2500"W".`
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