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Question
Which of the following pairs represent units of the same physical quantity?
Options
Kelvin and joule
Kelvin and calorie
Newton and calorie
Joule and calorie
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Solution
Joule and calorie
One calorie is defined as the amount of heat needed to raise the temperature of 1 g of water from 14.5° to 15.5° at the pressure of 1 atm. Heat is a form of energy and the unit of energy is joule.
Therefore, joule and calorie represent energy.
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