Since 50 efficiency is given, half of the energy of the falling water will be used by the bulbs. Therefore,
21ΔtΔmgh=n×P⇒21×36009×104×10×40=100n⇒n=50
Water falls from a 40m high dam at the rate of 9×104kg per hour. Fifty percentage of gravitational potential energy can be converted into electrical energy. Using this hydro electric energy number of 100W lamps, that can be lit, is
(Take g=10ms−2)
Held on 28 Jun 2022 · Verified 6 Jul 2026.
25
50
100
18
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