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Question
State (i) the S. I. unit, (ii) the household unit, of electrical energy. How are these units related?
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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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