$Assertion :$ Perspiration from human body helps in cooling the body.
$Reason :$ A thin layer of water on the skin enhances its emissivity.
$Reason :$ A thin layer of water on the skin enhances its emissivity.
AIIMS 2006, Easy
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Perspiration envolves exchange of heat from body to surrounding. Water takes heat from the body and gets converted into vapour. Hence, body cools down. A thin layer of water on the skin will reduce rather than increase its emissivity. So, Assertion is correct but Reason is incorrect.
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