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Question
A current of 2 A is passed through a coil of resistance 75 Ω for 2 minutes.
(a) How much heat energy is produced?
(b) How much charge is passed through the resistance?
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Solution
Given , current (I) = 2 A
Resistance R = 75 Ω
Time , t = 2 min = 120 s
(a) Heat produced , H = I2Rt
or , H = (2)2 (75)(120) J = 36000 J
(b) Charge passed , Q = It
or, Q = (2)(120) C = 240 C
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