Assertion : When a glass of hot milk is place | vedclass

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(B) The entropy change of a system is given by $dS = \frac{dQ}{T}$. When a body cools,it loses heat,so $dQ$ is negative. Since $T$ is positive,$dS$ is

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If both $Assertion$ and $Reason$ are correct but $Reason$ is not a correct explanation of the $Assertion$.

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(B) The entropy change of a system is given by $dS = \frac{dQ}{T}$. When a body cools,it loses heat,so $dQ$ is negative. Since $T$ is positive,$dS$ is negative,meaning the entropy of the milk decreases. Thus,the $Assertion$ is correct.The second law of thermodynamics states that the total entropy of the universe (system + surroundings) must increase for any spontaneous process. The cooling of a hot object in a room involves an increase in the entropy of the surroundings that is greater than the decrease in the entropy of the system,so it does not violate the second law. Thus,the $Reason$ is also correct.However,the $Reason$ explains why the process is possible,not why the entropy of the milk itself decreases. Therefore,the $Reason$ is not the correct explanation of the $Assertion$.

$Assertion :$ When a glass of hot milk is placed in a room and allowed to cool,its entropy decreases.
$Reason :$ Allowing a hot object to cool does not violate the second law of thermodynamics.

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$Assertion :$ When a glass of hot milk is placed in a room and allowed to cool,its entropy decreases.$Reason :$ Allowing a hot object to cool does not violate the second law of thermodynamics.