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Question
An electric heater is connected to the 230 V mains supply. A current of 8 A flows through the heater.
(b) How much energy is transferred to the heater each second?
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Solution
Here, potential, V = 230 V
Current, I = 8 A
Energy transferred = Work done, W
Using the relation, V = W/Q:
W = V x Q
= 230 x 8 = 1840 J
Thus, 1840 joules of energy is transferred to the heater each second.
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