: How does a fan work against the heat?
In: Other
A fan doesn’t actually cool the air, it simply moves it around. But that has two effects when it blows on you. Firstly it blows away the layer of air that has been warmed by your body heat and replaces it with cooler air in the room. Secondly it allows more evaporation from moist skin, again blowing away the air that has picked up moisture and replacing it with less saturated air that can take up moisture by evaporation. The process of vaporization requires heat to change liquid to gas, which comes from your body which therefore loses that heat.
The first effect works for any hot body, e.g. the microprocessor in your computer. The second only applies to wet things and if the air isn’t already saturated with moisture, so it is less effective in a 100% humidity situation.
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