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3 light bulbs 3 switches

  1. Apr 14, 2005 #1
    You are in a room with 3 switches which correspond to 3 bulbs in another room and you don't know which switch corresponds to which bulb. You can only teleport to the room with the bulbs and back once. You can NOT use any external equipment (power supplies, resistors, etc.). How do you find out which bulb corresponds to which switch?

    I found two answers to this one I am sure there are a ton more.

    Oh and no making up dumb stuff like saying the wires connecting the switches and bulbs are all differant colors and then using that to get your answer. :mad:
  2. jcsd
  3. Apr 14, 2005 #2
    Answer (highlight):Flip one switch on and wait a minute. Flip it off and flip another switch on. Teleport to the room. The switch you just flipped corresponds to the light that's on. Feel the two bulbs that are off. The switch you flipped first corresponds to the hot bulb, while the switch you never flipped corresponds to the room-temperature bulb.
  4. Apr 15, 2005 #3
    i think we've had it a couple of times before. anyways my answer is the same as above.
  5. Apr 15, 2005 #4
    My answer is the same as the above, above post.

    The Bob (2004 ©)
  6. May 1, 2005 #5
    Coincidentally, my answer is the same as the above x3. :tongue2:
  7. May 1, 2005 #6
    Old riddle =)
  8. May 8, 2005 #7
    I have a different answer.

    Turn one switch on and off for a few years and then switch another one on and teleport to the room. The one that's burned out was the first switch, the one that's on is the second switch, and the one that's off is the unused switch.

    Another solution...

    Turn on one light and leave it on for awhile at night for a month, then turn it off and turn on the second switch. Teleport there and the one that has dead bugs underneath it is the first one that was on. The light that's currently on is the second switch... etc...

    Although... that's in reality. This may not be reality... in which case none of your answers would work either because what if flipping the switch up turns it off instead of on, and what if that's the case with all the switches, or if that's the case with only 1 or 2 of the switches. Or maybe 1 or more of the bulbs are burned out already. Anyway... just for fun anyways... :tongue2:
  9. Jan 27, 2011 #8
    use the iPhone app that allows you to turn on/off lights remotely
  10. Jan 27, 2011 #9
    Three more ways I made up.

    1. Put one of the switches half way between on and off. You can do this by hearing the electrical contact zapping when the small distance between them makes sparks. Turn one of the lights on. The flickering bulb is the half switch and the other two are easy.
    2. Turn on one bulb, wait 3 seconds, and as you turn on another instantly teleport to the room. If it was instant you have enough time to see if one of the bulbs warmed up to full luminosity or not.
    3. Same thing but turn one off and teleport to see if it's transitioning to on-off.
  11. Mar 1, 2011 #10
    same as hypermorphism
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