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?
I would use an assistent! I would enter the room and wait, he would turn on and off the first switch, after one minute, he'll do the same to the next switch, then after one more minute, proceed with the last switch. Then I would go out of the room and know what switch was conected to the bulb, because the time it took to be lit. The problem doesn’t say nothing about assistants and nothing about the time I’d spend in the room, says only i could enter the room once. So I did it.<o:p></o:p>
what about an assistant?
