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NEET UG PHYSICS MCQ: WORK-ENERGY-POWER

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A mass of 50 kg is raised through a certain height by a machine whose efficiency is

90\%

, the energy is 5000 J. If the mass is now released, its KE on hitting the ground shall be

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Correct option: B

4500 J

Option B (4500 J) is correct because the machine's efficiency is 90%, so the useful energy (potential energy gained) is 90% of the input energy (5000 J). When the mass is released, this potential energy converts to kinetic energy, hence KE = 0.9 * 5000 J = 4500 J.

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