Which of the following options represents only the units of energy?
Show answer & explanation
Correct answer: D
Explanation
The correct answer is option 4 i.e. Joule, Calorie, Kilowatt hour.
All three—Joule, Calorie, and Kilowatt-hour (kWh)—are units of energy.
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Joule (J) is the SI unit of energy.
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Calorie is a non-SI unit, commonly used in measuring food energy (1 calorie = 4.184 joules).
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Kilowatt-hour is used to measure electrical energy (1 kWh = 3.6 million joules).
These units measure the capacity to do work or produce heat, making them pure energy units.