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Question
A 720 W heater operates from a 220 V line voltage. Calculate:
(a) The electrical energy consumed by the heater in 3 h.
(b) The cost of electrical energy consumption at the rate of 60 paise per kWh.
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Solution
Given, power P =720 w= 0.72 kW
Voltage, V = 220 volt
(a) Electrical energy consumed in 3 h = 0.72 x 3 = 2.16 kWh
(b) Cost of energy consumption @60 paise per kWh= 2.16 x Rs 0.6 =Rs 1.3
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