There is a room with one bulb turned off. There are three switches outside. You cannot see inside in any way, and you can only open the door once. How can you tell which switch turns on the light?
2006-09-04 15:01:36 · 14 answers · asked by philisophical 1 in Education & Reference ➔ Trivia
Maybe i wasn't clear. NONE of the light switches say ANYTHING.
2006-09-04 15:07:18 · update #1
And once the door is open, you cannot turn any of the switches on or off
2006-09-04 15:08:29 · update #2
Open the door. Then check each switch one at a time. :-)
Edit - based on your addtl info:
Akeja looked like he/she was on right track, but confused the situation with the porch light. Here's the simple solution.
1) turn on switch 1 and 2, wait 2 min
2) turn off switch 2
3) open door
a) if light is on, switch 1 is answer
b) if light is off and bulb is hot, switch 2 is answer
c) if light if off and bulb is cold, switch 3 is answer
Have a great day!
2006-09-04 15:06:35 · answer #1 · answered by Yada Yada Yada 7 · 7⤊ 1⤋
There are 3 switches, therefore there are 3 bulbs - you mentioned that one bulb was not turned on but didn't specifically mention that there's only one bulb in the room.
Since only one bulb is turned on, the other 2 are & therefore two switches will be in the different position from the 3rd switch which will in turn give away the answer as to the switch that would turn the bulb in question on.
2006-09-06 05:14:02 · answer #2 · answered by Kevin F 4 · 0⤊ 0⤋
turn on switch 1 and 2 for about 5 min. then, turn off switch 1 and open the door. if the light bulb is on, then switch 2 is it. if not, touch the light bulb. if it is warm, then the switch is #1 because a light bulb heats up. if it is not warm, then it has to be switch 3
right?
2006-09-04 15:14:00 · answer #3 · answered by Anonymous · 3⤊ 0⤋
Turn on two of the switches let's say No.1 and No.2 for the purpose of this explanation) and turn the third switch (No.3) off.
Wait about ten minutes. Turn off No.1 and turn on No.3. Now, head for the porch.
If the light is off, No.1 controls the porch light. Problem solved!
If, however, the light is on, either No.2 or No.3 controls the porch light. To determine which one, touch the light bulb. If the bulb is hot, No.2 controls the porch light; if the bulb is cold, it is Switch No. 3.
2006-09-04 15:09:37 · answer #4 · answered by Akeja 5 · 2⤊ 1⤋
Easy.
Open the door first, then leaving it open, try the switches one at a time.
2006-09-04 15:08:50 · answer #5 · answered by NEIL C 2 · 2⤊ 0⤋
break the window, turn on each switch till the light comes on and then once you get it, smile and walk in through the door and enjoy the light that the bulb provides :)
2006-09-04 15:10:58 · answer #6 · answered by Ryan 2 · 1⤊ 1⤋
Open the door and then try the switches individually.
2006-09-04 15:09:16 · answer #7 · answered by crispy critter 2 · 2⤊ 1⤋
why do I have to close the door at all. Why can;t I go back and forth.
I assume you meant that the door will close behind me after I leave so that I cant actually tell.
Anyhow.
I have no idea.
I hope there is a real answer and not some BS
2006-09-04 15:09:26 · answer #8 · answered by billyandgaby 7 · 2⤊ 2⤋
turn 2 on at a time
2006-09-04 15:07:36 · answer #9 · answered by Anonymous · 0⤊ 1⤋
Lift each switch just a little bit carefully and slowly across it's full range and listen for the arcing crackly sound of very slightly separated contacts. (You can try this at home.)
It sounds like this....
000000010001001011011101111111
2006-09-06 17:36:19 · answer #10 · answered by Anonymous · 0⤊ 1⤋