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I am in a room which is heated up duringg day, in night outside temp is quite low, but my room with a ceiling fan running still feels hot as it was in day if I step outside door its cold. There is only one door and window to room. Why room is not getting cold like outside? Wont ceiling fan throw air and it will move out of room ?

there is approx 6-7 deg C difference. Room is made of concrete and bricks

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The perception of temperature is determined to air temperature but also by radiation temperature. The roof and walls of your room are heated up by absorption of sunlight during the day to a high temperature. This could easily reach 80 celsius. On the inside they will emit infrared radiation corresponding to this temperature. The total radiation energy emitted is proportional to $T^4$ in Kelvin, so this is a significant effect. The IR is absorbed by your body and raises its temperature. A fan will only help you cool by making transpiration more effective. In the morning the walls should have cooled down and your room should feel more comfortable. When you walk outside this IR radiation is replaced by that of a dark sky, which emits a much smaller radiance.

The solution is to paint the roof white, and even better, to thermally insulate roof and walls.

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The structural components of the room (walls, floors, etc.) and, to a lesser extent, furniture and appliances, store heat. It could take quite some time for all this heat to go away. In the meantime, it'll keep the air in the room warm.

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