What is power? How do you differentiate kilowatt from kilowatt hour? The Jog Falls in Karnataka state are nearly 20 m high. 2000 tonnes of water falls from it in a minute. Calculate the equivalent power if all this energy can be utilized? (g = 10 m s–2)
ScienceClass 9CBSEAnswered 27 Mar 2026
Answer
Soln:
Power is the rate of transfer of energy or rate of doing work. Watt is the unit of power and kilowatt is 1000 watts.
h = 20 m, and mass = 2000 × 103 kg
= 2 × 106 kg
Power = m g h / t
= 2 x 106 x 10 x 20
60
w = 4x107w =
6
2 x107w
3
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