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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.
Solution
Given, current, I= 0.2 A; p.d. = 15 V
(i) A/C to Ohm's law
V=IR
R = `"v"/"I" = 15/0.2 = 75 Omega`
(ii) energy produced in one minutes is:
H=I2 Rt = (0.2)2 x 75 x 60 =180 J
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