Solve the Lightbulb Puzzle with One Trip

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    Lightbulb Puzzle
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Discussion Overview

The discussion revolves around a logic puzzle involving three switches and three corresponding lightbulbs in a separate room. Participants explore how to determine which switch controls which lightbulb with only one trip into the room with the lightbulbs.

Discussion Character

  • Exploratory, Debate/contested, Homework-related

Main Points Raised

  • One participant proposes a method involving turning on switches 1 and 2, waiting for a period, and then checking the state and temperature of the bulbs to identify which switch corresponds to which bulb.
  • Another participant acknowledges the proposed method and indicates they will use the suggestion in future discussions.

Areas of Agreement / Disagreement

There is no explicit agreement or disagreement noted among participants, but the second post presents a specific solution while the first post invites others to think about the problem, suggesting that multiple approaches may be considered.

Contextual Notes

The discussion does not address potential limitations of the proposed solution or assumptions about the conditions of the lightbulbs and switches.

Who May Find This Useful

Individuals interested in logic puzzles, problem-solving strategies, or those looking for creative approaches to similar challenges may find this discussion useful.

Herodotus
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You're in a room with three switches that open three lightbulbs in a separate room. You don't know which switch turns on which lightbulb. How do you find out which switch goes to which lightbulb by entering the other room only once? You don't have any help, you can't see the other room while you are in the room with the other switches or vice versa, you can't make any device that extends your reach into the other room, etc.
 
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If the switches are numbered 1, 2 and 3, do this:

Start with all switches off.
Turn on switches 1 and 2.
Wait 5 minutes.
Turn off switch 2.
Go into the other room.

The light that is on corresponds to switch 1.
The light that is off and warm corresponds to switch 2.
The light that is off and cold corresponds to switch 3.
 
James R said:
If the switches are numbered 1, 2 and 3, do this:

To give other people a chance to think about the problem, check out the "eye" icon in the editor menu:

It helps the people who do not want to see the answer skip your posted solution.
 
Ah. Ok. I'll use that in future.
 
This is a test of the eye function - DO NOT READ under penalty of law.
 

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