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a) Power = V2 / R = (240 × 240) / 100 = 576 W
b) P = V I =>> I = P / V = 576 / 240 = 2.4 A
c) P × t = heat supplied = (m c ${\theta}$) = 576 × t = 0.2 × 4200 × 72. Hence t = (0.2 × 4200 × 72) / 576 = 105 seconds.
d) Cost = kWh × cost per unit = (0.576 × 2 × 30) × 5.0 = Ksh 172.80
Mutiso answered the question on October 16, 2018 at 18:15
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