Q22 of 146 Page 163

An electric heater uses 600 kJ of electrical energy in 5 minutes. Calculate its power rating.

Energy = 600KJ = 600000J;

Time = 5 min = 5 x 60 = 300s


Power = Energy/ Time


= 600000/300


Power = 2000W


Therefore, Power of electric heater = 2000W


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