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# Bulbs

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You could also walk into the room and have someone else turn on/off each switch. It never said you couldn't recruit help.

From the puzzle: "No help from anybody else is allowed."

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While in the room with the switches, turn one light on and leave it on for a while to get the light hot. Turn the light off and switch any other switch on. Then go into the room with the lights. The bulb that is off but still warm was the first switch, the cold bulb is the switch you did not turn on and of course, the bulb that is on is the switch you turned on.

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My Solution is this... assuming all light bulbs are the "standard" type... turn on 2 switches... wait 5 minutes... turn one off... go feel which bulb is still hot.... done... all 3 bulbs have different characteristics.. Dark, Hot, Light

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I didn't see this idea so I'm posting it.

1) Turn on one switch and walk into the room and identify which lamp is on (one down...two to go).

2) Unscrew one of the bulbs in the lamps that are not lit up.

3) Assuming you can tell that a light has been turned on standing where the switches are, turn the other two switches on and off to determine which one has the unscrewed bulb (the other two should be identifiable at this point).

That should give you the ability to identify all switches to their lamps with one room entry.

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Thats not logical at all this is the stupidest puzzle I have ever read. It seems no one notices that the author states in the last line that you may enter the room with the bulbs only once. If you left one light on and went in there and felt it you wouldn't necessarily be able to distinguish which switches went to the other 2 bulbs. Then he says in the answer that you would have to go back and forth a few times. What a waste of time. One replied with a staggering the time at which you turn the light out which seems right to me and she was right it took 2 second to think about.

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Thats not logical at all this is the stupidest puzzle I have ever read (don't hesitate to post your favorite puzzles in this forum). It seems no one notices that the author states in the last line that you may enter the room with the bulbs only once. If you left one light on and went in there and felt it (touch - get closer with your hand - not to the bulb that is on BUT to the bulbs that are off) you wouldn't necessarily be able to distinguish which switches went to the other 2 bulbs (you actually would). Then he says in the answer that you would have to go back and forth a few times (where exactly have I written that? pls highlight the part). What a waste of time. One replied with a staggering the time at which you turn the light out which seems right to me and she was right it took 2 second to think about.

Bulbs - Back to the Logic Puzzles

This is one of my favorite logic puzzles (Edit: it is more a practical than a logic puzzle).

Imagine you are in a room with 3 switches. In an adjacent room there are 3 bulbs (Edit: let's say in lamps which are on a regular table) - all are off at the moment, each switch belongs to one bulb. It is impossible to see from one room to another. How can you find out which switch belongs to which bulb, if you may enter the room with the bulbs only once?

Edit: No help from anybody else is allowed.

Edit: Find out which switch belongs to which bulb - identify all 3 switches (so find out what bulbs are switches 1, 2 and 3 connected to)

Bulbs - solution

Keep the first bulb switched on for a few minutes. It gets warm, right? So all you have to do then is ... switch it off, switch another one on, walk into the room with bulbs, touch them and tell which one was switched on as the first one (the warm one) and the others can be easily identified ...

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What if not all the lights are off when you start?

then its almost impossible

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Fist make on 1 switch. keep it on for 5 min. so whatever its connectd bulb will be got hot.

Then off that sitch.

then on other swith. so its respective bulb will be on.

now solution is. the current on bulb is respective to current on switch.

off hot bulb is respective to previous on swith.

and rest is third one.

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All you would have to do is turn one switch on for a while to let the bulb heat up, then turn it off turn the next one on, then go into the room. The one that is hot is the first switch, tyhe one that is on is the second, and the one that is off is the third.

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I have a solution that doesn't involve any temperature! You, definitely dont have to burn your hand or anything!

1. Turn on 1 switch.

2. Go in the room, uninstall one of the two other light bulb.

3. Go out, turn off the 1st switch.

4. Turn on 1 of two other, if there is light in the next room, that switch is for the light bulb that is still there, otherwise it's for the light bulb you take out.

That's it!

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It is probably simple. First switch on one bulb for a while. Swith it off. Then switch on another and keep the other in off position. When you enter the room, warm bulb belongs to first switch, one glowing to the second, and one in switch off mode is the third.. Did I get correct.

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turn switch one on for 60 seconds.

turn switch one off and turn switch two on.

walk in the room.

the warm bulb belongs to switch one, the lit bulb belongs to switch two and the cold bulb belongs to switch three.

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Turn on 1 of the switches. Let it sit for a while. Turn it off. Turn another switch on. Go into the other room. The light that is on is run by the switch you just turned on. Feel the other two. The one that is warm is run by the switch you first flipped. The cold light is the third switch.

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turn one switch on = light bulb on

leave one switch off = light bulb off

turn one switch on then off just before you enter the room = bulb that is warm to the touch

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when you enter the room place three different colored bulbs in each socket qand then you can see what color matched each swith I would assume you can atleast see the lights color from the other room

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1st - Number switches 1,2,3.

2nd- Turn and keep switch 1 on, Turn switch 2 on for about a minute, Keep switch 3 off.

3rd - Go next door light 1 will be on, Light 2 will be warm but off, Light 3 will be off and cold.

Thus only going into room once and you will have correctly identified the 3 switches to the 3 lights.

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Bulbs - Back to the Logic Puzzles

This is one of my favorite logic puzzles (Edit: it is more a practical than a logic puzzle).

Imagine you are in a room with 3 switches. In an adjacent room there are 3 bulbs (Edit: let's say in lamps which are on a regular table) - all are off at the moment, each switch belongs to one bulb. It is impossible to see from one room to another. How can you find out which switch belongs to which bulb, if you may enter the room with the bulbs only once?

Edit: No help from anybody else is allowed.

Edit: Find out which switch belongs to which bulb - identify all 3 switches (so find out what bulbs are switches 1, 2 and 3 connected to)

Bulbs - solution

Keep the first bulb switched on for a few minutes. It gets warm, right? So all you have to do then is ... switch it off, switch another one on, walk into the room with bulbs, touch them and tell which one was switched on as the first one (the warm one) and the others can be easily identified ...

smart

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you could turn one light on go in and see. and take a mirror with you because it never said you couldnt use any objects to help you. you would then have to angle the mirror with the switches from the bulbs. pretty easy if you think about it

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Alternatively:

-1 switch off = bulb off

-1 switch on = bulb on

-1 switch halfway (yes you can do this) = bulb dim & flickering

that would be so much easier than touching hot bulbs

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Switch A,B,C. Lamp X,Y,Z.

Turn on Switch A for 5 minutes. Turn of A. Turn on B. Go to the room. If X is on then X belongs to B. Feel Y and Z. If Y is warm then Y belongs to A. Then Z must be belong to C.

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Very Simple, turn on one switch and leave one switch off, and tun one switch on for a few minutes and then turn it off. Go into the next room. There will be one cool bulb off for the switch that was never turned on, there will be one bulb on for the switch you turned on and then there will be one bulb that will still be warm or hot for the switch you turn on momentarily.

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fosley, your comment cracked me up and rookie1ja, this is an old riddle but i still couldn't get it!

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turn of switch 1 leave it on for 2-3 min (long enough for it to get hot) then turn it off. turn of switch 2. go into the room. if the light bulb is hot but off it is switch 1. it the light bulb is on it is switch number 2. if the light bulb is off and cold then it is switch 3. Ta Da!

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well u could turn one on, then when ur done with it throw it on the ground real hard. youll kno if that bulb was turned on before by checking the bottom of your red feet.....

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I comply, it is not the logical puzzle

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