JEE Main 2022PhysicsWork Power EnergyMediumMCQ

JEE Main 2022 — Work Power Energy Question with Solution

JEE Main 2022 (28 Jun Shift 2)

Question

Water falls from a 40 m high dam at the rate of 9×104 kg per hour. Fifty percentage of gravitational potential energy can be converted into electrical energy. Using this hydro electric energy number of 100 W lamps, that can be lit, is
(Take g=10 ms-2)

Choose an option

Show full solutionCorrect option: B
Correct answer
B50

Step-by-step explanation

Since 50% efficiency is given, half of the energy of the falling water will be used by the bulbs. Therefore,

12∆mghΔt=n×P⇒12×9×1043600×10×40=100n⇒n=50

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About this question

This is a previous-year question from JEE Main 2022, covering the Work Power Energy chapter of Physics. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.