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Question
Find the heat produced in joules when a current of 10 amperes flows through a connecting wire of resistance 2 × 10-2 ohms and heating element of resistance 250 ohms for 2 seconds.
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Solution
Heat produced when current flows in the wire for 2 seconds
Q1 = I2Rt
Q1 = 10 × 10 × 2 × 10-2 × 2
Q1 = 4 J
Heat produced in heating element in 2 seconds
Q2 = 10 × 10 × 250 × 2
Q2 = 50000 J
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