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Question
How do kilowatt and kilowatt-hour differ?
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Solution
| Kilowatt | Kilowatt-hour | |
| i. | Power in electrical kilowatts is its SI unit. | Commercial electrical energy is measured in kilowatt-hours. |
| ii. | The amount of energy expended in a single second. | A power appliance uses 1 kW of energy in 1 hour. |
| iii. | 1 watt = `(1 "J")/(1 "S")` | 1 kWh = 3600000 J |
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