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Question
State (i) the S. I. unit, (ii) the household unit, of electrical energy. How are these units related?
Solution
(i) The S.I. unit of electrical energy is joule (J)
(ii) The household unit of electrical energy is kilo-watt hour (kWh).
Relationship: 1 kWh = 1 kW × 1h
= 1000W × 3600 s
= 3.6 × 106 J.
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