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        riddles >> easy >> Light Bulbs & Switches Variation
        
(Message started by: alien2 on Aug 24th, 2013, 5:25am)
Title: Light Bulbs & Switches Variation
Post by alien2 on Aug 24th, 2013, 5:25am

You are in a room with three light switches, each of which controls one of three light bulbs in the next room. You know which switch is initially on whereas two switches are off.  Two ceiling bulbs are out of reach while one is the hanging bulb. Your task is to determine which switch controls which bulb. You can't see into one room from the other. You are allowed only one chance to enter the room with three light bulbs. How can you determine with certainty which light switch goes with which light bulb?
Title: Re: Light Bulbs & Switches Variation
Post by Grimbal on Aug 26th, 2013, 7:53am
I think you can't.

There is no way to make sure that the 2 bulbs out of reach are not both on or both off.  If it happens, there is no way to tell them apart.
Title: Re: Light Bulbs & Switches Variation
Post by alien2 on Aug 26th, 2013, 8:44am
You can determine with certainty which switch goes with which bulb.
Title: Re: Light Bulbs & Switches Variation
Post by gotit on Aug 26th, 2013, 10:45am
Are we allowed to take something with us inside the room with light bulbs?
Title: Re: Light Bulbs & Switches Variation
Post by gotit on Aug 26th, 2013, 10:57am
I was thinking about [hide]manipulating the connections i.e Switch 1 -> Switch 2, Switch 2 -> Switch 3 and Switch 3 -> Switch 1. And if the two unreachable bulbs are in the same state, I was thinking that perhaps we can tell them apart based on the temperature of the hanging bulb[/hide] . But it's too late in the night too think anymore. Will resume thinking tomorrow, unless someone comes up with a solution.
Title: Re: Light Bulbs & Switches Variation
Post by alien2 on Aug 28th, 2013, 12:56am

on 08/26/13 at 10:45:24, gotit wrote:
Are we allowed to take something with us inside the room with light bulbs?

Nope.
Title: Re: Light Bulbs & Switches Variation
Post by rmsgrey on Aug 28th, 2013, 4:36am
[hide]Trace the wires[/hide]?
Title: Re: Light Bulbs & Switches Variation
Post by alien2 on Aug 28th, 2013, 5:04am
Nah, man. :P ::)
Title: Re: Light Bulbs & Switches Variation
Post by gotit on Aug 28th, 2013, 8:02am
Use [hide]color[/hide] to differentiate between the two out of reach bulbs.
Title: Re: Light Bulbs & Switches Variation
Post by alien2 on Aug 28th, 2013, 8:27am
All three are identical and standard light bulbs.
Title: Re: Light Bulbs & Switches Variation
Post by gotit on Aug 28th, 2013, 8:50am
If a bulb glows for too long, it might create a dark patch on the bulb or on the wall around it. May be that can help.
Title: Re: Light Bulbs & Switches Variation
Post by alien2 on Aug 28th, 2013, 11:53am
I see. You cannot be certain it will work.
Title: Re: Light Bulbs & Switches Variation
Post by Grimbal on Aug 30th, 2013, 1:48am
The light bulbs that are out of reach, can you still tell whether they are hot or not?
Title: Re: Light Bulbs & Switches Variation
Post by alien2 on Sep 8th, 2013, 5:41am

on 08/30/13 at 01:48:03, Grimbal wrote:
The light bulbs that are out of reach, can you still tell whether they are hot or not?

You can't tell whether they are hot or cold.


The riddle is tricksy. (http://www.youtube.com/watch?v=RXMunYFRfgk)
Title: Re: Light Bulbs & Switches Variation
Post by Grimbal on Sep 8th, 2013, 1:36pm
OK, then.

You tamper with the wires so all switches control all lamps.  (each switch reverses the state).

Or you cut all wires.  Now, you know which switch controls which bulb: none of them does.
Title: Re: Light Bulbs & Switches Variation
Post by alien2 on Sep 8th, 2013, 2:03pm
Your answers are not correct but still they made me laugh so I thank you. ;D
Title: Re: Light Bulbs & Switches Variation
Post by swapnilraja1212 on Sep 17th, 2013, 12:31am
Looks a bit complex question. Could you please answer it now.
Title: Re: Light Bulbs & Switches Variation
Post by alien2 on Sep 17th, 2013, 3:25am
I will say the answer if necessary, but not today. Give it time. There are no omitted objects. Just consider what is said in the riddle. You should put a certain part of the riddle under the magnifying glass though.
Title: Re: Light Bulbs & Switches Variation
Post by gotit on Sep 17th, 2013, 6:51am

on 09/17/13 at 03:25:45, alien2 wrote:
You should put a certain part of the riddle under the magnifying glass though.


Okay. So first time you enter the room. The next time you stand outside the room and peep in.  ;D
Title: Re: Light Bulbs & Switches Variation
Post by alien2 on Sep 22nd, 2013, 12:49am
Not even close.
Title: Re: Light Bulbs & Switches Variation
Post by Grimbal on Sep 22nd, 2013, 1:50am
Do you start the riddle in the room with the light bulbs?  I.e. you are there twice but you enter it only once, when you return.

Can you ask someone else to enter the room?

Do you have an RC drone?

Do you use mirrors?

Do you have any means to sense any property of the light bulbs without being inside?

Do you have such a long arm that you can play with the switches from the next room?

Is the magnifying glass important?
Title: Re: Light Bulbs & Switches Variation
Post by Nursejim on Sep 22nd, 2013, 6:18am
Maybe like the riddle says....... Each switch controls "one" light bulb so whichever one is on when you walk in is controlled by all three switches. Just a guess. These riddles are addicting! :)
Title: Re: Light Bulbs & Switches Variation
Post by Grimbal on Sep 23rd, 2013, 3:15am
Can you sense the heat of a lamp bulbs that is out of reach for example by spitting on it?  Or by using infra-red goggles?
Title: Re: Light Bulbs & Switches Variation
Post by alien2 on Sep 23rd, 2013, 7:05am

on 09/22/13 at 06:18:44, Nursejim wrote:
Maybe like the riddle says....... Each switch controls "one" light bulb so whichever one is on when you walk in is controlled by all three switches.

Nice try! :D Alas, each switch controls a different bulb. Keep thinking like that.


on 09/22/13 at 01:50:05, Grimbal wrote:
Do you have any means to sense any property of the light bulbs without being inside?

Only if you are a psychometrist. Just kidding. You are on the right track.  


on 09/22/13 at 01:50:05, Grimbal wrote:
Do you have such a long arm that you can play with the switches from the next room?

LOL.
Title: Re: Light Bulbs & Switches Variation
Post by Grimbal on Sep 23rd, 2013, 7:53am
Pull on one of the wires (where the switch is off).  The corresponding bulb is the one that is now touching the ceiling.
Title: Re: Light Bulbs & Switches Variation
Post by alien2 on Sep 23rd, 2013, 9:12am
You don't have tools for that. Use your mind, eyes and fingers.  
Title: Re: Light Bulbs & Switches Variation
Post by 0.999... on Sep 23rd, 2013, 1:33pm
If we swing the hanging bulb like a pendulum, could we hit one of the other bulbs?
Title: Re: Light Bulbs & Switches Variation
Post by alien2 on Sep 24th, 2013, 2:10am
Nice try. You could unscrew the bulb, break the glass and throw the screw base. Or you could just throw your shoe.

You needn't break the bulbs.
Title: Re: Light Bulbs & Switches Variation
Post by gotit on Sep 24th, 2013, 3:32am
Use the [hide]shadow of your fingers[/hide] to determine which bulb is glowing
Title: Re: Light Bulbs & Switches Variation
Post by Nursejim on Sep 24th, 2013, 6:10pm
Awe! Use the what?  >:(   ;)
Title: Re: Light Bulbs & Switches Variation
Post by gotit on Sep 25th, 2013, 7:08am

on 09/24/13 at 18:10:55, Nursejim wrote:
Awe! Use the what?  >:(   ;)


The angle at which the [hide]shadow[/hide] of your fingers is formed might help in determining which bulb is glowing.
Title: Re: Light Bulbs & Switches Variation
Post by Grimbal on Sep 25th, 2013, 8:54am
We are going nowhere.  Is the following description correct?

The problem runs in 2 phases:

1. you are in the "3 switches" room and you manipulate whatever switches you like, but during that time the "3 bulbs" room is completely sealed off, that means you cannot sense anything from there, no indirect light, no sound, no heat thru the wall or whatsoever.

2. you enter the "3 bulbs" room and can examine whatever you want.  But 2 of the bulbs are out of reach.   In this phase, the "3 switches" room is out of reach, you cannot flip any switch, not even remotely as for example with a thread or using a device attached to a timer.

Correct?


PS: the switches and the bulbs are not labeled clearly telling which bulb goes with which switch, right?
Title: Re: Light Bulbs & Switches Variation
Post by alien2 on Sep 25th, 2013, 9:22am

on 09/25/13 at 08:54:01, Grimbal wrote:
1. you are in the "3 switches" room and you manipulate whatever switches you like, but during that time the "3 bulbs" room is completely sealed off, that means you cannot sense anything from there, no indirect light, no sound, no heat thru the wall or whatsoever.

2. you enter the "3 bulbs" room and can examine whatever you want.  But 2 of the bulbs are out of reach.   In this phase, the "3 switches" room is out of reach, you cannot flip any switch, not even remotely as for example with a thread or using a device attached to a timer.

Correct?

That is correct.


on 09/25/13 at 08:54:01, Grimbal wrote:
PS: the switches and the bulbs are not labeled clearly telling which bulb goes with which switch, right?

There are no such labels.



I'm having a lot of fun. I guess I have a mean streak. Perhaps I'd be depressed if you found the intended answer lame.


Once you eliminate the impossible, whatever remains, no matter how improbable, must be the truth.  
Title: Re: Light Bulbs & Switches Variation
Post by Nursejim on Sep 25th, 2013, 11:46pm
Is this the plot for the next "SAW" movie?! :D Why dont we just ask the owner of the building whats what.
Title: Re: Light Bulbs & Switches Variation
Post by alien2 on Oct 4th, 2013, 1:35am
You must deduce on your own which switch goes with which bulb.

Nothing said in the riddle is [hide]accidental.[/hide]
Title: Re: Light Bulbs & Switches Variation
Post by Nursejim on Oct 5th, 2013, 12:39am
Ok this should work! You leave the switch on that was already on, calling it #1. We must leave it on for 10 mins at least. That will mean the corresponding light bulb will be very hot. So hot it will burn you to touch it. So now you flip on # 2 switch but only for say 30 secs to minute. That will make it pretty warm but noticeably cooler than #1. Now at exactly the same time you flip off switch# 1,2 and turn on #3 and run into room. 3 bulb will be the one thats on brightly. #1 bulb will still have a residual glow of the filament because of the high heat so that will leave the other bulb as #2. The easiest way this can work is if the hanging bulb is not on when you go in to investigate and you can just judge by touch. Very hot=1, medium=2, on always= 3. As long as you remember the order you will know which bulb goes with which switch!!  :P
Title: Re: Light Bulbs & Switches Variation
Post by alien2 on Oct 5th, 2013, 3:28am
Nice try. These lightbulbs don't continue to glow after the light is turned off.
Title: Re: Light Bulbs & Switches Variation
Post by Nursejim on Oct 5th, 2013, 10:55pm
But my theory of judging is possible, just not in all possible scenerios. Oh well back to drawing board. Between the two emotionally disturbed towers and this one I have got a headache.
Title: Re: Light Bulbs & Switches Variation
Post by Nursejim on Oct 6th, 2013, 10:07pm
Are you going to ever post the answer? Just askin. Clue maybe
Title: Re: Light Bulbs & Switches Variation
Post by alien2 on Oct 7th, 2013, 2:37am
There's more to the [hide]2nd sentence than meets the eye.[/hide]
Title: Re: Light Bulbs & Switches Variation
Post by Grimbal on Oct 7th, 2013, 6:56am
"You know which switch is initially on whereas two switches are off."
Does it mean what it usually means?  I.e. "which switch" is in terms of the physical switch, and not in terms of the lamp it controls"

So you are not told something like: the switch to the 3rd lamp is on.  Right?
Title: Re: Light Bulbs & Switches Variation
Post by siddharthan5335 on Oct 7th, 2013, 3:02pm
Going by the 2nd sentence, I know which switch is intially on - meaning I am in the bulbs room at this point of time. If I where in the switches room, this statement is not necessary.

I observe which light it is. note it down. I only exit the bulbs room now. I turnoff that bulb and switch on any one of the two remaining. I enter the bulbs room and observe ( entering once) .

Is this is what there is more to second statement than meets the eye?
Title: Re: Light Bulbs & Switches Variation
Post by Grimbal on Oct 8th, 2013, 8:54am
You did not reply to:
Do you start the riddle in the room with the light bulbs?  I.e. you are there twice but you enter it only once, when you return.

Anyway, you can switch the light on and off many, many, I mean, very many times.  My mom always told me it spoils the bulb.  So you do it long enough to blow the lamp and then you turn a second switch.  In the room you can see which lamp blew, there is a dark spot.  And the second is the one that's on.

On the other side, maybe my mom just wanted me to stop.  So maybe it is better to leave the lamp burning for 10 years.
Title: Re: Light Bulbs & Switches Variation
Post by alien2 on Oct 8th, 2013, 2:40pm
You start in the room with the switches. They bring you to this room and tell what your task is.


on 10/07/13 at 06:56:46, Grimbal wrote:
So you are not told something like: the switch to the 3rd lamp is on.  Right?

You are told nothing like that. You have to [hide]deduce on your own which bulb is on.[/hide]
Title: Re: Light Bulbs & Switches Variation
Post by Nursejim on Oct 8th, 2013, 9:14pm
Well is there any chance that the switches have dimmers on them? That would make it easy!
Title: Re: Light Bulbs & Switches Variation
Post by alien2 on Oct 9th, 2013, 3:32am
Here's the answer: By applying logic, you deduce that [hide]the switches are in prearranged order on/off. So the switch that is initially on must control the hanging bulb.[/hide]

What do you think? Is the intended answer logical, a bit lame or lame? Tell the truth.
Title: Re: Light Bulbs & Switches Variation
Post by Grimbal on Oct 10th, 2013, 4:28am
That is not logical, it is a conclusion based on a wild guess.  You assume that the switch was on for a reason and that the reaseon is that the lamp is hanging lower.
Title: Re: Light Bulbs & Switches Variation
Post by alien2 on Oct 10th, 2013, 11:13am
How dare you! When I was writing the riddle, there was a man in my house. I fought with this man. He had a mechanical arm. You find this man. You find this man. (http://www.youtube.com/watch?v=ZQ11Ws3tqP0)

You broke my heart Grimbal. (https://www.google.hr/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&ved=0CC0QtwIwAA&url=http%3A%2F%2Fwww.youtube.com%2Fwatch%3Fv%3DFcFlp6kl508&ei=2NpWUo7eCYm14ASK6IDIBg&usg=AFQjCNFK73ylMF4BdkbhSVA_zzL_yVul2g&bvm=bv.53760139,d.bGE)

Heartless must he your favorite movie. (http://en.wikipedia.org/wiki/Heartless_(2009_film))

Instead of telling me the cruel truth, you could've encouraged me. You could've lied to me by telling me that my riddle is amazing and that I have a beautiful mind. You could've told me that Big Brother, the roommate Charles and the little girl are imaginary. What is the matter with you? You sure are subtle. When I said that you tell me the truth, you didn't have to take it literally. (http://www.youtube.com/watch?v=or65M4Ht4Kk)

I guess Vulcans would deport me from the planet Vulcan, eh?
Title: Re: Light Bulbs & Switches Variation
Post by Grimbal on Oct 10th, 2013, 3:04pm
Err... OK, Your riddle is amazing.  You have a beautiful mind.  Big Brother, the roommate Charles and the little girl are imaginary.  What is the matter with me.  I sure am subtle.  When you said that I tell you the truth, I don't take it literally.
Title: Re: Light Bulbs & Switches Variation
Post by alien2 on Oct 11th, 2013, 2:37am
You are very kind. Because of your encouragement, I am writing a similar riddle that is also very logical.
Title: Re: Light Bulbs & Switches Variation
Post by rmsgrey on Oct 11th, 2013, 6:52am

on 10/10/13 at 15:04:58, Grimbal wrote:
Err... OK, Your riddle is amazing.  You have a beautiful mind.  Big Brother, the roommate Charles and the little girl are imaginary.  What is the matter with me.  I sure am subtle.  When you said that I tell you the truth, I don't take it literally.

You crazy fool! Look what you've done!

on 10/11/13 at 02:37:04, alien2 wrote:
You are very kind. Because of your encouragement, I am writing a similar riddle that is also very logical.



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