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Question
Calculate the quantity of heat that will be produced in a coil of resistance 75 Ω if a current of 2A is passed through it for 2 minutes.
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Solution
R = 75 Ω, i = 2A, t = 2 minutes = 2 × 60 s = 120 s
Heat energy produced in the coil, H = i2Rt
= 22 × 75 × 120
= 300 × 120 = 36000 J
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