Which one of the following is the unit of electrical energy?
(a) Watt
(b) Ohm
(c) Kilowatt-hour
(d) Volt
WBBSE
Class X
Physical Science
Current Electricity
01 Mark
2025
(c) Kilowatt-hour
Explanation:
Electrical power is defined as work done per unit time, while electrical energy is power × time, commonly measured in watt-hour or kilowatt-hour (kWh) in domestic consumption. The Board of Trade unit used in household electricity bills is one kilowatt-hour, which is the practical unit of electrical energy.
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