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प्रश्न
Derive an expression for the amount of heat given out or taken up, when its temperature falls or rises by t°C.
उत्तर
Let the mass of the body be ‘m’ and its specific heat capacity be ‘s’. It t°C is the rise in its temperature, then heat taken up by the body is calculated as below:
Since ‘s’ is the specific heat capacity of the body which means that the unit mass of the body for a rise of 1°C takes up ‘s’ amount of heat.
∴ Mass ‘m’ of the body for a rise of t°C will need heat
= m × s × t
= Mass of the body × Its specific heat × Rise in the temperature
= mst joule.
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