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Question
An electric kettle of 2 kW is used for 2h. Calculate the energy consumed in
- kilowatt hour and
- joules.
Solution
(i) Power, P =
So, energy consumed, E = P × t = 2 × 2 = 4 kWh
(ii) Energy consumed, E = 4 kWh
= 4 × 1000 × 3600 J
= 1.44 × 107 J
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