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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?
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Solution
Power, P = 2 kW
Power, `P = "Work done (W)"/"Time Taken (T)"`
⇒ W = P × 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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