3 Switches, 1 Light Bulb

3 Switches, 1 Light Bulb

Put on your engineering hat for this fun brain teaser.

Engineers are know to be some of the smartest individuals in the world, but even they stumble across problems and situations that put their knowledge to test. 

Here is this week's brain teaser:

In front of you are three light switches. Only one does anything, and it turns on the light downstairs. From here you can't see the light, and it makes no sound. You must determine which switch operates the light, BUT you can only go check it once. How do you figure out which switch is for the light? 

Keep scrolling to reveal the answer.


Flip any switch you want. Wait for about 5-10 minutes to let the bulb heat up. Flip that same switch off, and another one on. Go check the light. If it's off and hot, it was the first switch, if it's on it was the second and if it's cold and off, it was the last one.

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What makes the light bulb turn on?

Electrical testing is paramount to the safety of people and equipment, and efficiency of any business entity. Learn about Electrical Testing and how it helps protect against dangerous situations.