$Assertion :$ When a glass of hot milk is placed in a room and allowed to cool, its entropy decreases.
$Reason :$ Allowing hot object to cool does not violate the second law of thermodynamics.
$Reason :$ Allowing hot object to cool does not violate the second law of thermodynamics.
AIIMS 2006, Easy
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A body cools, its entropy decreases as $dS = \frac {dQ}{T}$ and $dQ$ is $-ve, dS$ is also $-ve$. $R$ is also true. Second law states that entropy of the universe increases. Universe includes both system and surroundings. $R$ does not explain $A$.
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