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# Bulbs

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This one is easy. Turn on switch #1 and wait for 1 minute. Turn off that switch and flip on switch #2. Now go into the room. If the bulb is on, it is switch #2. If it is not, touch the bulb. If the bulb is warm, it is switch #1. If the bulb is cold, it is switch #3.

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C.

So you turn on a switch (we'll call it switch A) for a few minutes then turn it off, immediately turn on the next switch (we'll call this one switch B) and the other switch © will remain untouched in the off position. When you enter the room with the bulbs, you will notice one that is on, this correlates to switch B. Next you will place your hand next to the bulbs that are not on. The warm bulb will correlate to switch A, and the last bulb will correlate to switc

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1. Turn on switch 1 and wait for an hour(or however long a lightbulb takes to get hot)

2. After an hour, Turn on switch 2 and run into the light bulb room

3. Touch the two light bulbs and the one that is really hot is switch one, the one that is not hot since it was just turned on is switch two

4. The light bulb turned off is obviously switch 3

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I think that I would take the lamps back to the first room and then turn them on, since the puzzle didn't say that the cords wont reach and that I may enter the first room as many times as I want this seems to be an easy solution for a difficult problem

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One switch is turned on for a few minutes before being switched off

A second switch is turned on and I enter the room with the lamps.

The lamp with the lit bulb belongs to the 2nd switch and of the remaining lamps,

the warmest belongs to the first switch. By elimination, the third switch is

connected to the remaining bulb.

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1. Turn on switch 1 and wait for an hour(or however long a lightbulb takes to get hot)

2. After an hour, Turn on switch 2 and run into the light bulb room

3. Touch the two light bulbs and the one that is really hot is switch one, the one that is not hot since it was just turned on is switch two

4. The light bulb turned off is obviously switch 3

Close, but not quite...

Have you ever seen how quickly an incandescent light bulb heats up? Given that it would take you at least a couple seconds to move from one room to the other, and that you might not even pick the bulb that was just turned on first, I don't think anyone would be able to tell the difference between a bulb that has been on for an hour and one that has been on for 20 seconds.

However, the bulbs cool much more slowly, so it is far easier to tell the difference between a bulb that was hot 2-3 minutes ago and one that has been turned off for hours...

"After an hour, turn off switch 1, turn on switch 2, and run into the light bulb room"

and step 3 becomes:

"Touch the 2 light bulbs that are off. The one that is still warm is switch 1, the one that is cold is switch 3, and the one that is still on is switch 2".

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This one is easy.....turn one switch on for about 10 mins, turn it off. Then turn a different one on and go in the other room. The light that is on is obviously the one you left on. Feel the other two and whichever one is warm is the switch you left on and then turned off.

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This is easy.

Turn on two switches. Wait a moment, then turn one off. Whichever is on when you enter the room with the lamps is the one you left on. The second one should be warm and that is the one you switched off. The third is cold and is connected to the switch you didn't touch.

Thomas J. Clancy

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I am assuming the bulbs are normal 'filament' type that produce heat and light both.

Now , Just switch two switches, wait for some time and then turn off one of them.

walk into the next room.

We can see one bulb that is lit - This belongs to the switch that is on

Now, assuming that the rooms are close enough, one of the two bulbs would be at a temperature more than the room temperature. This would belong to the switch that we just turned off.

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Turn on the first switch for a short time and then turn it off. Leave the second switch off. Turn on the third switch and leave on. When you enter the room with the lamps, the one with a warm bulb belongs to the first switch, the one with a cold bulb belongs to the 2nd switch, and the one with the lit bulb belongs to the 3rd switch.

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Turn two switches on, wait a minute turn one off resulting in one switch turned on, the other two turned off, go to the other room and you will see that the light that is on is controlled by the switch that is on, the warm light bulb is controlled by the second switch that was turned on then later turned off, and the remaining switch controls the cold lightbulb.

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Turn on one switch then switch it off and turn on another one & enter the room the bulb which is off and warm is the one you switched on and off, the one that is off is for the switch which you didnt switch on ...................

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Turn-On the first bulb.

Turn-Off the second bulb

Turn on the third bulb after a while(say after 5 min)

The bulb which is most hottest is the first bulb.

The bulb which is coldest is the second bulb.

The bulb which is mild hotter is the third bulb.

Cracked....

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To determine which switch activates each bulb turn on the first two switches, assuming they are in a horizontal line. Wait a few minutes, enough time to allow the bulbs that have been switched on time to warm up. Then turn off the second switch, leaving only the first switch on. enter the room. The bulb that is on is connected to switch one. The bulb that is off, but warm to the touch is connected to switch 2. The bulb that is off and cool/cold is connected to switch three, the switch which was never turned on.

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Switch on two blubs for at least 10 minutes. Switch one of the two off. Then enter the room to discover which switch corresponds to the lit bulb, which switch corresponds to the 'warm' just turned off bulb and finally the third unused switch will match up with the coldest bulb. Under the principle that electricity gives off heat, this method will work!

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I agree with earlier comments that it's rather strange to see people bothering to post the solution again after it has already been posted and discussed many times.

Anyway, I've decided the 1-switch-on-at-a-time solution posted by the site admin is better than the two-on-then-one-of-these-two-off variation because the former is more energy efficient (assuming the same bulb warmup times).

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You turn on the first switch, then turn it off. You wait 5 minutes, turn on the 2nd switch leave it for 5 minutes then turn it off. Then immediately (without waiting 5 min. like last time) turn on the next switch. Walk into the room. Which ever bulb is cold, and off belongs to the 1st switch. Whichever bulb is hot, but off belongs to the second switch. Whichever bulb is on belongs to the 3rd switch! Ta da! Now you people can sleep again! Haha!

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Maybe I could just look through the door at the light bulbs without actually going into the room to see the bulbs.

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Maybe I could just look through the door at the light bulbs without actually going into the room to see the bulbs.

check wording of the puzzle again ...

It is impossible to see from one room to another.

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Turn on one switch.

Go in to the room and unplug/unscrew one of the unlit bulbs.

Go back to the switches and turn on one of the remaining switches.

If a bulb goes on or off tells you which switch belongs to which.

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turn off 1 switch wait 1 min

turn off 2nd switch

wait 30 sec

go into room

bulb on is switch on (3)

buld cold is switch 1

bulb warm = switch 2

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This one's quite simple, really. I like it. It makes me feel smart. Here we go...

--Assume the switches and lamps are in a respective row; left, center, and right.--

step one: turn on one switch for a few seconds remembering which switch it was. For systematic's sake, let's call it the left switch.

step 2: After about fifteen to twenty seconds, turn that switch off.

step 3: Turn aqnother switch on. Let's say that this one's the center switch. Leave it on.

step 4: Leave the switch room and enter the bulb room quickly.

step 5: With one bulb on, touch the two bulbs that are off.

conclusion:

center switch = bulb that is on

right switch = bulb that is cold

left switch = bulb that is warm

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Turn switch number one on. Turn switch number two on. Leave switch number three off. After one minute turn switch number two off. Go into the other room and the bulb that is off and cold is wired to switch number three. The bulb that is off and warm is wired to switch number two. The bulb which is lit, is wired to switch #1.

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first, you turn on the first switch. then, you wait about a minute or so. then, you turn the second switch on and walk into the room. you touch all the light bulbs and the one that is hot is the one that belongs to the first switch. the one that is on belongs to the second switch. the one that isn't hot or on belongs to the third switch.

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Simple. Turn on one switch. Enter bulb room and verify which bulb. Unscrew another bulb. Return to switch room and hit another. Result will indicate which bulb for that switch.

Thanks

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