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Question
A current of 0.2 A flows through a wire whose ends are at a potential difference of 15 V. Calculate:
(i) The resistance of the wire, and
(ii) The heat energy produced in 1 minute.
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Solution
Given ,
Current, I = 0.2 A
Potential difference , V = 15 V
Time ,t = 60 sec
As V = IR
(a) R = `15/0.2 = 75 Omega`
(b) Heat energy , H = I2Rt
H = (0.2)2 × 75 × 60
or H = 180 J
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