Have you figured out how to tell which switch controls the light? You can see the original question here.
Flip switch number 1 and wait a few minutes. Flip switch number 1 back to its original position, and then immediately flip switch number 2.
Open the door. If the light is on, then switch number 2 controls it. If the light is off, then go and feel the bulb with your hand. If the bulb is hot, the switch number 1 controls it, and if the bulb is cold, then switch number 3, the one you did not touch, controls it.
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Jay Bennett is the associate editor of PopularMechanics.com. He has also written for Smithsonian, Popular Science and Outside Magazine.