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Question
Find the energy in joules consumed in 10 hours by four devices of power 500 W each.
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Solution
The power of four devices = 4 × 500 W
= 2000 W
Time = 10 hours
Therefore,
The energy consumed = power × time
= 2000 × 10 Wh
= 20000 Wh
= 20 kWh
= 20 units. ...[1 unit = 1 kWh]
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