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प्रश्न
How can electric energy consumed by an electric appliance be calculated in kilowatt hour (kWh)?
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उत्तर
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`
संबंधित प्रश्न
Name the physical quality which is measured in
(i) Kw (ii) kWh
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| Sr.no. | Name | Nos. | Power rating | Time/day |
| 1 | Bulb | 4 | 100 W | 7.5 hr |
| 2 | Fans | 2 | 50 W | 10 hr |
| 3 | T.V. | 1 | 100 W | 2 hr |
| 4 | Iron | 1 | 500 W | 1 hr |
| 5 | Electric stove | 1 | 750 W | 2 hr |
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