Post:

You have three switches in one room and a single light bulb in another room. You are allowed to visit the room with the light bulb only once. How do you figure out which switch controls the bulb? Write your answer in the comments before looking at other answers.

Comment:

If this were an interview question, the correct response would be "Do you have any relevant questions for me? Because have a long list of things that more deserving of my precious time than to think about this!

  • fruitcantfly@programming.dev
    3·
    4 hours ago

    Well, maybe you’d better wait 10min instead of one, to make sure the led lightbulb heats enough, but still…

    I tested this with a 5W IKEA LED light-bulb, since I was just doom scrolling, anyway:

    • After 1 minute of being on, the bulb was still room temperature.
    • After 10 minutes of being on, the bulb was lukewarm.
    • After 10 minutes of being off, the bulb was room temperature, though the fitting maybe felt slightly warmer. That latter will probably depend on your installation, and how well it is able to disperse the heat.

    This means that the solution either breaks down entirely, or is unreliable, since you are not (reliably) able to tell the first two buttons apart