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#1 unreality

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Posted 15 February 2008 - 01:43 AM

There are ten Super-Self-Cooling light bulbs in a room. To prevent loss of unnecessary heat energy, they are specifically designed to instantly cool themselves down when turned off. In fact they try to cool themselves when turned on as well, to make sure their circuit doesn't break, and the bulbs are made of a resilient glass that can't shatter.

You are in a room with a closed door leading into another room where these ten bulbs are. You can control the ten light bulbs from the room you are currently in. You have to be able to tell which bulb corresponds with which dial.

Yes, dial. Fortunately for you, each Super-Self-Cooling lightbulb isn't a simple on-off switch. It's a dial, with settings from 0 to 4 to level the brightness. Yep, 5 levels of brightness... since there are ten bulbs, it should be easy, right? Wrong. Not that it would be easy anyway, with 5 settings for 10 bulbs, but there's more: The circuitry is screwed up. One of the dials is useless, and another dial controls its own light bulb as well as the light bulb that used to correspond with the useless dial- so one dial controls nothing and another dial controls two light bulbs at once. There are two cases like that! Two useless dials, two doubled-up dials. There is no way to figure out beforehand which dials are useless or not, all the rewiring problems are above the other room.

Since your job is to figure out how each of the 8 working dials with 5 setting levels affect the 10 bulbs, what do you do?

Spoiler for MUHAHAHAHA!

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#2 TwoaDay

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Posted 15 February 2008 - 01:56 AM

if you cant go back and forth, get someone to help you
Why not?
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#3 Jkyle1980

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Posted 15 February 2008 - 02:50 AM

How many times are you allowed to adjust the knobs and check the lights?

And when you say 0 - 4 are the settings, five levels of brightness, is 0 really really dim or off?
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#4 bonanova

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Posted 15 February 2008 - 05:51 AM

Hate to spoil this so quickly, but I just made a drawing, with switches 1-10 and bulbs A-J
Spoiler for It was really easy. They paired up like this:
All seriousness aside, I'm working on it.
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The greatest challenge to any thinker is stating the problem in a way that will allow a solution.
- Bertrand Russell

#5 Jkyle1980

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Posted 15 February 2008 - 06:19 AM

There are ten Super-Self-Cooling light bulbs in a room. To prevent loss of unnecessary heat energy, they are specifically designed to instantly cool themselves down when turned off. In fact they try to cool themselves when turned on as well, to make sure their circuit doesn't break, and the bulbs are made of a resilient glass that can't shatter.

You are in a room with a closed door leading into another room where these ten bulbs are. You can control the ten light bulbs from the room you are currently in. You have to be able to tell which bulb corresponds with which dial.

Yes, dial. Fortunately for you, each Super-Self-Cooling lightbulb isn't a simple on-off switch. It's a dial, with settings from 0 to 4 to level the brightness. Yep, 5 levels of brightness... since there are ten bulbs, it should be easy, right? Wrong. Not that it would be easy anyway, with 5 settings for 10 bulbs, but there's more: The circuitry is screwed up. One of the dials is useless, and another dial controls its own light bulb as well as the light bulb that used to correspond with the useless dial- so one dial controls nothing and another dial controls two light bulbs at once. There are two cases like that! Two useless dials, two doubled-up dials. There is no way to figure out beforehand which dials are useless or not, all the rewiring problems are above the other room.

Since your job is to figure out how each of the 8 working dials with 5 setting levels affect the 10 bulbs, what do you do?

Spoiler for MUHAHAHAHA!


I believe there is no solution if playing by the normal light bulb riddles. There are only 5 possible settings that I can think of because you removed all other distinguishable characteristics other than off, 1, 2, 3, and 4. Four settings for ten bulbs cannot be solved in one trip. In fact, I don't believe it can be solved in two trips. And with 3 trips, it's too easy.
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