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प्रश्न
How is kilowatt hour related to joule?
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उत्तर
1 kWh is the work done by a source of power 1 kW in 1 h, i.e.,
1 kWh = 1 kW × h = 1000 J s-1 × 3600 s = 3.6 × 106 J
1 Kilowatt hour = 3.6 × 106J
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