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Question
In a hydroelectric power station, 1000 kg of water is allowed to drop through a height of 100 m in 1 sec. If the conversion of potential energy to electric energy is 60%. Calculate the power output. [Take: g = 10m/sec2]
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Solution
In a hydroelectric power station:
Mass of water (m) 1000 kg.
Height (h) = 100 m.
Time (t) = 1 sec.
Produced potential energy (P.E.) = mgh = 1000 × 10 × 100 JouIe
= 1000000 joule
Electrical energy = 60% of potential energy
`=60/100xx1000000`
= 600000 joule
Power output = Energy × Time
= 600000 × 1 watt
= 600000 watt
=`600000/1000` kilo-watt
= 600 kilo-watt.
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