$Assertion :$ It is hotter over the top of a fire than at the same distance of the sides.
$Reason :$ Air surrounding the fire conducts more heat upwards.
AIIMS 2003, Easy
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It is hotter over the top of a fire. It is because of convection current established over the fire. As air warms up, its density decreases as a result of which it goes up and makes upper layer of air hot. The Reason is incorrect.
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