Q51 of 54 Page 135

5 appliances are used 10 hours per day in a house. Out of which 2 appliances are of 200 w and three are of 400 W. Then calculate the amount electric energy consumed in units.

Power of the appliances = 200W , 400W


= 0.2kW, 0.4kW


Power consumed by the 200W appliances = 2 x 10 x 0.2 = 4 kWh = 4 units


Power consumed by the 400W appliances = 3 x 10 x 0.4 = 12 kWh = 12 units


Total power consumed by the 5 appliances = 4 + 12 = 16 units


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