The luckiest thing that’s every occurred is said to be our very existence. We’re in the perfect solar system. We’re the perfect distance away from the sun. We’re in a habitat with the perfect surroundings, both inanimate and animate. We’ve been created through the perfect series of evolutions, formed by a phenomenal combination of stardust. That’s said to be the luckiest thing ever to occur. But it’s not. The luckiest thing ever to occur is me, as a first year student, inherited an air-conditioned suite. Others must cool their rooms with simple box fans…and that led me to thinking, how, actually, does a fan even cool a room?

Box fans (and every fan in general) are said to cool off rooms. That’s why we keep them turned on when the air temperature is hot. To cool rooms, the fans complete a simple task: spinning. Moving the air. And the room gets colder. Simple…right? That’s what I’d figured upon thinking about it all.

Heat is defined as being a measure of the average kinetic energy of particles. The more movement matter has, in unison with this definition, the more kinetic energy the matter has. Utilizing logic, we can then arrive at the widely accepted statement that heat is caused by movement. Makes sense, righ-

Wait.

Fans…that cool things off…cause movement…in the air. But we  just established movement causes heat. So…how do fans, by causing more kinetic energy, cool things down? The simple answer comes from a physicist in Houston: they don’t.

Fans, if left in an unattended room, do not decrease the temperature. Instead, they actually raise it (just minutely, by less than a degree or two). But regardless, if fans raise the temperature, why do we use them and how do they cool us off?

The answer, actually, is much more simple than one would assume. Of course, even as non-scientists, we should know by now that nature’s unwavering fetish is to obtain equilibrium. One’s body is naturally trying to make the surrounding air the same temperature. One’s body does this by sweating. Whether discrete or in bucket loads, the sweat continues to pour from pores until the immediate, surrounding air reaches 100% humidity and collaterally becomes the same temperature as the body.

This is where fans become effective through two terms- the wind chill effect, which leads to convective heat loss. This wind chill effect is the exact same phenomenon weathermen talk about in regards to blowing wind. The fan moves air over you, and in that process, it takes the air your body heated away, too. This causes convective heat loss. This causes your body to feel colder in the absence of surrounding heated air. This causes more evaporation to the moving air. This causes your body to be colder…and is why fans are effective. They don’t create cold- they just move warm air away from the skin. After all, cold doesn’t even exist. The absence of heat does.

In lending advice to those less-fortunate than I (freshmen without A/C), scientific research has proven leaving fans running in an unventilated, unattended room, to be futile. In your absence, it’ll only heat the room for your return. The only exception is if the fan is running for the purposes of mixing nearby cooler air, in which case, it would be effective to leave the fan running by a door or by a window. Otherwise, the fan is useless if you aren’t around and if it isn’t blowing on you.

At this point, it’s likely you’ve realized fans will be the most two-faced interaction you have all year; they’ll be cooling air when you’re around and heating it when you aren’t.

-By Isaac Will