A geyser of 2 kW heats water. Time to raise temperature of 5 kg water from 30°C to 50°C (specific heat 4200 J/kg°C) is MCQ with Answer and Explanation

A geyser of 2 kW heats water. Time to raise temperature of 5 kg water from 30°C to 50°C (specific heat 4200 J/kg°C) is
A. 210 s
B. 840 s
C. 105 s
D. 420 s
Answer: Option A
Solution (By JKSSB Mock Tests)
Heat required Q = m c ΔT = 5 × 4200 × 20 = 420,000 J. Power 2000 W, time t = Q/P = 420000/2000 = 210 s.

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