3 Switches



There are three light switches on a wall, one of the switches controls a light 
upstairs, the other two switches control lights that you can not see.  You can 
only go upstairs once. How do you figure out which light switch controls the 
light upstairs. 
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Answer:
Turn on the first switch and leave it on for about a minute then 
turn it off, then turn on the second switch and immediatly go 
upstairs, if the light is on it is the second switch, if the light 
is off, feel the lightbulb if it is hot, then it was the first switch, 
if it is not hot then it is the third switch.