Question
Express watt hour and kilowatt hour in joule.
✓
Answer
$1 kWh = 1W \times 1 hour = 1000 W \times (60 \times 60) s$
$= 1W \times 1s \times 10^5 \times 36 = 36 \times 10^5 J = 3.6 \times 10^6 J$
$= 1W \times 1s \times 10^5 \times 36 = 36 \times 10^5 J = 3.6 \times 10^6 J$
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