Q34 of 146 Page 163

Derive the relation between commercial unit of energy (kWh) and SI unit of energy (joule).

The relation between commercial unit of energy (kWh) and SI unit of energy (joule) is-

1kWh = 1000 W × 1h.


1 watt = 1 joule/1 sec


= 1000 × 60 × 60


= 3.6 × 106J


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