A light bulb is hanging in a room. Outside of the room there are three switches, of which only one is connected to the lamp. In the starting situation, all switches are off and the bulb is not lit.

You are allowed to enter the room only once (the bulb is not visible from outside). How can you determine which of the three switches turns on the light bulb?

simple..you switch on 1 bulb and leave it on for say an hour then switch on the second and leave it on for 5mins and not on the last.when u go in to the room the bulb thats the warmest is the first one u switched on the 2nd warmest is the second and the cold one is the last one the on you didnt switch on

Posted by nas on 2003-01-14 07:31:37