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Question
Find the energy released by a current of 0.25 amperes flowing through a heater for 5 minutes. The p.d. is 230 V.
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Solution
V = 230 volts; t = 5 minutes = 60 × 5 = 300 s, I = 0.25 amperes
W = VIt = `230 xx 25/100 xx 300`
W = 17250 Joules
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