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Question
A certain household has consumed 250 units of energy during a month. How much energy is this in joules?
Solution
Total energy consumption during the whole month = 250 minutes
1 unit = 1kWh
250 unit = 250 kWh
= 250 × 1000 Wh
= 250 × (1000 W) (3600 s)
= 250 × 1000 × 3600 W s
= 900 × 106
= 9 × 108J
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