A gas heater raises temperature of 1kg of water by 30°C in 10min. How long will it take the same heater to raise 3kg of oil through the same temperature rise if the specific heat of water is twice that of oil (assuming that there is no heat loss)
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Question

A gas heater raises temperature of 1kg of water by 30°C in 10min. How long will it take the same heater to raise 3kg of oil through the same temperature rise if the specific heat of water is twice that of oil (assuming that there is no heat loss)

Options

G1 Physics · Accepted Answer

Apply energy conservation. Sensible heat is Q=mcΔT and phase-change heat is Q=mL. Heat lost by hotter parts equals heat gained by colder parts. Evaluating the given data/statements gives A: 15 min. Therefore the correct answer is A.