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प्रश्न
What is the commercial unit of electrical energy? Represent it in terms of joules.
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उत्तर
The commercial unit of electrical energy is Kilowatt hour (kWh)
1 kWh = 1000 W × 1 h
`1 "kWh" = 1000 "J"/"s" × 3600 "s"`
1 kWh = 3.6 × 106 J
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