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Question
How can electric energy consumed by an electric appliance be calculated in kilowatt hour (kWh)?
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Solution
The electric energy in kWh van be calculated as follows:
Energy in kWh = `("Power" ("in watt") xx "Time"("in hour"))/1000`
or kWh = `("V"("volt") xx "i" ("ampere") xx "t" ("hour"))/1000`
∴ Energy (in kWh) = `"Vit"/1000`
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