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Question
Define watt-hour. How many joules are equal to 1 watt-hour?
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Solution
Watt hour is a smaller commercial unit of electric energy, which is spent by an electric appliance of 1 watt power in 1 hour, i.e.
1 watt hour = 1 watt × hour = 1 watt × (60 × 60)s
= 3600 joule.
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