Power developed by a person on eating 100g of ice per minute is (Latent heat of ice is 80 cal/g):
Correct answer: C. 560 J/sec
- A. 130 W
- B. 560 cal/sec
- C. 560 J/sec
- D. None of these
Explanation
Power = (mass per second) × latent heat.m = 100 g / 60 s = 5/3 g/s, so energy rate = (5/3×80) cal/s = 400/3 cal/s.Converting to joules: (400/3)×4.2 ≈ 560 J/s.Hence power ≈ 560 W, option C.
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Work transfers energy when a force causes displacement, while kinetic energy, gravitational potential energy and power describe motion, position and the rate of energy transfer. The work-energy theorem links net work with change in kinetic energy, and efficiency accounts for energy losses rather than treating them as energy destruction.
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