Question

Here's little brainteaser for you people:

You're standing in front of a room with one lightbulb inside of it. You cannot see if it is on or off. Outside the room, there are 3 switches in the off positions. You may turn the switches any way you want to. You stop turning the switches, enter the room and know which switch controls the lightbulb.

How?

Answer 1

Waaaaiiiitt... nothing was said about an inside switch! This is making my head hurt. lol

Answer 2

Can I just hire an electrician? ;)

Answer 3

wait let me rephrase my question once again @Luis_Rivera
You have a set of 3 light switches outside a closed door. One of them controls the light inside the room. With the door closed from outside the room, you can turn the light switches on or off as many times as you would like.

You can go into the room - one time only - to see the light. You cannot see the whether the light is on or off from outside the room, nor can you change the light switches while inside the room.

No one else is in the room to help you. The room has no windows.

Based on the information above, how would you determine which of the three light switches controls the light inside the room?

Answer 4

Only one controls the light, and the other 2 do nothing to the status of the light, correct?

Answer 5

This would be a lot easier if there were only TWO switches. I'd NAIL IT then! lol

Answer 6

Put a camera on the inside and were your done check the camera ;)

Answer 7

Very funny answers though :), theres no switch inside the room and "3" switches are there outside the room :)

Answer 8

@Luis_Rivera its not meant for living, its meant for thinking ( thats why theres no switch inside ) :P

Answer 9

Turn 2 switches "on" and leave 1 switch "off" and wait for about a minute. Then enter the room, but just before you enter, turn one switch from "on" to "off". Once in the room, feel the lightbulb - if it is warm, but off, it has to be the last switch you turned off. If it is on, it has to be the switch left on. If it is cold and is off, it has to be the switch you left in the off position.

Answer 10

LOL heck you @Luis_Rivera

Answer 11

Yeah..... yeah.... that's what I was about to say!! BRILLIANT! lol

Answer 12

@abb0t i see what you did there :P :P its the google right !!

Answer 13

I love how everyone is so interested in this question even though ti has nothing to do with math

Answer 14

im feared that i get banned for this question :P

Answer 15

i like to use my resources.

Answer 16

Hmm nice exploitation by the way :P

Answer 17

luis, you're 12. u cant even buy cigars.

Answer 18

Lol @Luis_Rivera your statement reminded me of film shawshank redemption :P

Answer 19

i think its not in that part lil before

Answer 20

wait i dint get any medals for asking this question !!!! :(

Answer 21

@SandeepReddy, wouldn't turning on all the switches ensure that the light bulb comes on? Are we assuming only one is connected to it?

Answer 22

yes only one is connected to it and we have to find that one switch in a single shot @SithsAndGiggles

Answer 23

Well you didn't say that the first time...

Answer 24

Any idea what the other two control?

Answer 25

not connected to anything just kept for testing .

Answer 26

so that it would become a brainteaser :)

Answer 27

@phi you could have left 2nd switch on .

Answer 28

easy, I open the door, get a prism and a mirror, have the prism reflect the light on to the mirror whose angle will reflect it back to the door, and I can try the switches about :P

Answer 29

you cant see whats in @jdoe0001 :)

Answer 30

but nice try though :P

Answer 31

well, that's what the prism and the mirror are for :)

Answer 32

I mean, this is an odd room, maybe Dr Who's dunno

Answer 33

haha