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Question
An electric pump has 2 kW power. How much water will the pump lift every minute to a height of 10 m?
Solution
Power, P = 2 kW
Power , `"P" = "Work done (W)"/"Time Taken (T)"`
⇒ `"W" = "P" xx "T"`
For every minute i.e. 60 s, work done by the pump is
`"W" = 2 xx 1000 xx 60 = 120000 "J"`
Now, this work is stored in water as its potential energy.
Thus,
mgh = 120000 J
⇒ m = `120000/(9.8 xx 10)` = 1224.5 kg
Hence, 1224.5 kg of water is lifted by the pump every minute to a height of 10 m.
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