Brain Teaser: 3 light switches

I’m borrowing a camera and wanted to play around with it. Everyone probably knows the answer to this old brain teaser already, but I thought this was pretty cool. If you’ve ever been to my house, you know where this light switch panel is found, so you probably have a guess as to how I came up with the inspiration for this shot.


In your cellar there are three light switches in the OFF position. Each switch controls 1 of 3 light bulbs on the floor above. You may move any of the switches but you may only go upstairs to inspect the bulbs once. How can you determine the switch for each bulb with one inspection?

Like how the picture coincides with the brain teaser? Awesome. Go me!


Penguingolfer89 September 23, 2003 Reply

Oh! Turn them all on!

Moviewatcher78 December 19, 2003 Reply

Turn on the first switch and wait a couple of minutes and then turn it off. Then, turn on the second switch and go upstairs. The light that is on is controlled by the 2nd switch. Feel the other two bulbs. The one that is warm is controlled by the 1st switch. The cool one is controlled by the 3rd switch. :)

Talk to me, Goose.

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