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प्रश्न
A water pump raises 50 litres of water through a height of 25 m in 5 s. Calculate the power of the pump required.
(Take g = 10 N kg-1 and density of water = 1000 kg m-3)
उत्तर
Mass of 50 litre of water = 50 kg
∵ 1cm3 of water = 1g
∵ 1000cm3 = 1 Lit. = 1kg
height = 25 m, t = 5 s, g = 10 Nkg-1
Power supplied by pump
= `(mgh)/t`
= `(50 xx 10 xx 25)/5`
= 2500 W
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