Question of the Day #32 - Let there be LIGHT!

[sxty8goats]

Question of the Day #32 Closed. 11/6/09 10:25AM

There is a room with a light bulb hanging from the ceiling.

There is nothing else in the room.

There are three light switches outside the room ,which one will turn on the light. The other two will turn on/off the lights in the old lady's house down the street. (obviously the previous home owner was a doosh)

You can only enter the room once.

You can not see into the room at all, not underneath door ,through the keyhole or over the door and there are no windows.

How can you figure out which light switch belongs to the room? #1,#2 or #3 ?

PM answers please.

Answer:


Turn on switch #1 and wait a few minutes for the bulb to get hot (if it turned the bulb on)
Turn off #1 and turn on #2
Enter the room.
If the light is on, it is switch #2
If the light is off and the bulb is warm it is switch #1
If the light is off and the bulb is cool it is switch #3

[hellmonkey]

Uh, I went with the obvious, but probably wrong approach.

[z_xxviii]

I probably said the same thing as you. Just doesn't seem like it could be right.

[Good Vibes]

I took a shot. Not sure if it's what you're looking for, though.

[2KSE]

I think I got it. pm sent.

[whaler01]

PM sent also, but my logic may be a bit off.

[1luckeyt/a]

pm sent. i think my answer is too obvious though.

[GTO48]

Late, but PM'd, and looking for some extra credit. ;)

[Laguna]

PM'd the most obvious.

[sxty8goats]

Well, this is going to piss of a few of you.

Closest Incorrect Answer: I would turn light switch 1 on and wait several minutes. Just before I was ready to enter the room I would turn light switch 2 on. If I enter the room and the light is not on, it must be switch 3 as 1 and 2 are on. If it is on quickly feel the lightbulb. If it is hot then it must be switch 1, and if it is just beginning to warm up it must be switch 2 because switch 2 was just turned on.

The bulb would heat up too quickly to know if it had been on 5 minutes or 1 minute. Very close though.

Points #32 Member
5 _ USCGTO
3 _ GoodVibes
2 _ SilverGoat04
1 _ 2KSE
1 _ BackRoadGTO
1 _ Go Steelers
1 _ VeritasGT
0 _ 1luckeyt/a
0 _ brada
0 _ burtonrider10022
0 _ bvbull200
0 _ d420gto
0 _ GTO48
0 _ hellmonkey
0 _ Laguna
0 _ whaler01
0 _ zxxviii

Nothing in the question indicates that:

You know where the old lady lives.

You can see her house from the position you would be in working the switch.

She would let you into her house to check her lights.

So she can not be used in this puzzle. A big part of solving logic puzzles is being able to ignore 'extra' information that is there to color the puzzle or throw you off.

Obvious solution: Open the door to the room, turn each switch on one by one and see which one works.
Nothing says you can reach or see the door from the switch position. The puzzle makes a point of saying that you can not see into the room at the same time you flip the switch.



Less obvious solution:

Beginning

Turn on one light switch you haven't turned on before. Walk your happy ass down to the old betty's house, and knock on the door. "Hey Grandma, are there ghosts in your house turning on lights and shit?"

If Grandma = "yes", return to switch panel, turn off switch then go to beginning.

If Grandma = "no" then end.

End.

:D

[hellmonkey]

Well, nothing in the problem states that the bulb is incandecent or halogen and that it would get warm. It could be an LED bulb or some other small light that wont get warm. But thats just me playin devils advocate.

[GTO48]

This question fails. :gr_jest:

[bvbull200]

Nothing in the question indicates that:

You know where the old lady lives.

You can see her house from the position you would be in working the switch.

She would let you into her house to check her lights.

So she can not be used in this puzzle. A big part of solving logic puzzles is being able to ignore 'extra' information that is there to color the puzzle or throw you off.

Nothing says you can reach or see the door from the switch position. The puzzle makes a point of saying that you can not see into the room at the same time you flip the switch.

I hope I don't come off as a whiny little brat, because this isn't really a complaint.

My contention with this is that there is also nothing to indicate that you can reach the lightbulb to tell if it is warm, so we are making an assumption that is no more logical than the assumption that you can go ask the lady if her lights flickered on and off. I'm sitting at my computer and can't think of a single light in this apartment that I could feel the warmth of without standing on a chair.

While the "old lady lives down the street" information is there to throw you off, I think it would be better if it weren't in the question. It gives the puzzle solver an out that isn't in the spirit of the question.

Oh well....I knew it probably had something to do with warmth, but I still couldn't figure out the "most correct" answer.

[JTSnooks]

Tuesday and no new question? Is 68 ok? Did he fall off of his chair when trying to tell if the lightbulb was hot?

[hellmonkey]

I think he needs more
http://www.prestoimages.net/store/graphics/648_pd2 28798_1.jpg

[sxty8goats]

Tuesday and no new question? Is 68 ok? Did he fall off of his chair when trying to tell if the lightbulb was hot?

I think he needs more
http://www.prestoimages.net/store/graphics/648_pd2 28798_1.jpg

Sorry folks, been out of life for a couple days. back soon.

[hellmonkey]

Sorry folks, been out of life for a couple days. back soon.

No prob, just let us know what her name is:-pimp:, unless









its a him:wall:

[Good Vibes]

Sorry folks, been out of life for a couple days. back soon.

That's ok. Just glad you're alright. :)

[d420gto]

That's ok. Just glad you're alright. :)

agree-

especially cause I sucked it up on the Friday questions

[5.7L FOREVER]

saweet although i havent pmed yet i just found this... its rather fun although i weetarted :boink: