A riddle for your brain: There are three light switches....

[ActiveMSers]

I just read about this problem, which requires one to use his or her creative side of the brain to solve. Can you figure it out? What's your answer?

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A room has three light switches. You can switch them on and off as you wish and then go to another room where there are three light bulbs. How can you identify which switch belongs to which light bulb? You cannot return to the room with the switches, the wall between the rooms is sealed, and the door is closed.
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Don't scroll too far or you might see the answer.

Don't scroll too far or you might see the answer.

Don't scroll too far or you might see the answer.

Don't scroll too far or you might see the answer.

Seriously, don't scroll too far or you might see the answer.

Don't scroll too far or you might see the answer.

Don't scroll too far or you might see the answer.

Don't scroll too far or you might see the answer.

Don't scroll too far or you might see the answer.

Don't scroll too far or you might see the answer.

Um, no, I'm not personally posting the answer...

[ActiveMSers]

I know this stretching every brain cell, but doesn't someone feel inspired to post the answer, or at least post "I got it". I'm just sayin'.

[Stella]

I've been racking my brain out Dave and I can't figure it out. The only thing that came to mind was lightbulb jokes

http://www.eyrie.org/~thad/strange/lightbulbs.html

[Lissie]

Ugh special moment shared.

[ActiveMSers]

Nice to meet, you Lissie! And thank you for the light bulb jokes. If you want a hint, these are incandescent bulbs, not LEDs.....

[Bigrushfan]

Thanks for the hint Dave. I racked my brain on Friday before heading off for some mountain hiking over the weekend in Northern Albania. Now that I am back, I think I have an answer. First, you switch on one light switch. When you go to the next room, the light that is on corresponds to that switch. Second, you switch on another light. You leave it one for a minute or two…..let the light bulb in the other room get nice and hot before you turn it back off. When you go to the other room, the light bulb that is off, but warm (hopefully not too hot) to the touch corresponds to that switch. You don’t touch the third switch and that is that. Tada! What a smart boy I am today. It must be that cup of coffee I just had. John

[AMFADVENTURES]

Thanks for the hint Dave. I racked my brain on Friday before heading off for some mountain hiking over the weekend in Northern Albania. Now that I am back, I think I have an answer. First, you switch on one light switch. When you go to the next room, the light that is on corresponds to that switch. Second, you switch on another light. You leave it one for a minute or two…..let the light bulb in the other room get nice and hot before you turn it back off. When you go to the other room, the light bulb that is off, but warm (hopefully not too hot) to the touch corresponds to that switch. You don’t touch the third switch and that is that. Tada! What a smart boy I am today. It must be that cup of coffee I just had. John

That's better than my answer, I was going to go into the light bulb room with some tools and parts and re-wire it all since I don't have a clue otherwise.

[ActiveMSers]

John, you get partial credit. Remember, you can't return to the room with the switches. But your general answer still works. Turn one switch on and leave it on for 15 minutes. Then turn it off and turn switch two, leaving switch three off. Enter the room: one light is on, two are off. The warm one is from switch one.

Phase 2: What if, because of your MS, you have zero temperature sensitivity? What do you do?

[Bigrushfan]

Dave,

Yes, I wasn't clear, but of course I meant that you would not go back into the room with the switches. You would complete everything first, and then go to the room with the light bulbs to solve the puzzle.

So, no sensitivity to temperature. I guess it is back to sight (assuming no blurry vision). I think, if you do the same steps as above you could still pull it off. You would need to run quickly, though, to the other room. I believe that the filament of the light bulb you switch on for 15 minutes might still be glowing red for a few seconds after the bulb is turned off. So, you would have one light bulb on in the room, one with a fading glowing red filament, and one off. Again, puzzle solved.

John

[ActiveMSers]

John, you get full credit for your original answer (my bad) and bonus points for your second, although that might be tricky. You could also rely on smell, as a warm bulb smells differently from a cold one. Heck you could even hold the hot bulb (even though you can't feel it) and then check your hands for redness/burning after 15 seconds.

Another completely different tangent to take would be to wait until the bulb burns out, turning one switch on and off for years. Finally turn one light on, leave the other off. Then go into the room and look for the telltale shadow or shake the two unlit bulbs to listen for that ring.

Nice work! BTW AMF, you get no credit, but I will call you when I do a little remodeling...

[AMFADVENTURES]

John, you get full credit for your original answer (my bad) and bonus points for your second, although that might be tricky. You could also rely on smell, as a warm bulb smells differently from a cold one. Heck you could even hold the hot bulb (even though you can't feel it) and then check your hands for redness/burning after 15 seconds.

Another completely different tangent to take would be to wait until the bulb burns out, turning one switch on and off for years. Finally turn one light on, leave the other off. Then go into the room and look for the telltale shadow or shake the two unlit bulbs to listen for that ring.

Nice work! BTW AMF, you get no credit, but I will call you when I do a little remodeling...

Rats, oh well, never was any good at that kind of stuff. I did have another idea though, punch a hole in the wall between the two rooms so you can look at the lights when you flip the switches . You don't have to travel between the rooms, just look through the hole.

Ready on the remodeling whenever you are.

AMF

[Bigrushfan]

Dave, Puzzles are good mental exercises for those of us with MS. Your's has multiple ways to solve it and reminds me of good story I heard many moons ago when I was training to be an English teacher for the Peace Corps:

http://www.mycoted.com/There_are_man..._test_question

I am sure many of you have heard this story before.

John

[ActiveMSers]

I like that story a lot, and you are dead-on with the importance of stretching your mind with MS.

A side note: that professor taught my mother when she went on the maiden voyage of Semester at Sea in 1963. I went in 1993 (different ship, obviously). Best thing I ever did by far.*

*Since it was also my honeymoon, I can wrap my marriage into the equation....