A Little Riddle

I heard this riddle yesterday and thought that ya'll might enjoy it.

So there is a room with three light switches in it. All of them are off. Down the hall there is another room with a light bulb, also off. Only one of the switches controls the bulb. You cannot in any way see the bulb or any light from it while in the room with the switches. You can travel to the room with the bulb only once. There is a way to arrange the switches so that when you are in the room with the bulb you can know for sure which switch controls the bulb. How will you do it?