Okay, this riddle has ALMOST gone on long enough....a couple of you have been getting 'warm,' but a more spelled-out hint seems called for.

As for knowing the answer AS SOON as the spy enters the room with the light bulbs, let's say he's got a full minute before he has to give his answer. This is true with Legolas's version as well. Now, here are the two important clues:

What properties can an incandescent light bulb have?

Legolas's statement of the problem said the riddle can be completed within 30 minutes, and the spy has all night to solve his....but he could easily do it in half an hour.

Here's one more, but more oblique hint: There is actually a solveable riddle where there are FIVE light bulbs, but the timeframe involved is longer than 30 minutes.....it's more like five years. (This hint is very closely tied to the previous two.)

Legolas, should we set a deadline before we give the answer?

I'll give this a shot..
If the spy cant leave the room with the switches, then how is he to enter the room with the lamp?
Its impossible since he can never EXIT the room with the lightbulbs until he ENTERS it.

Lets say that issint the answer and he CAN enter the room with the lightbulbs, but only once and cannot turn back to change his mind once he's in it.
A lamp provides illumination and heat..

Its a long shot but I'd say the spy would figure it out by reflecting on changes in temperature by touching the lightbulb when he enters the room. With only 4 switches to choose from, he could flip them one by one at regular intervals while taking note of the order in which he flips them. Then when he enters the room with the light bulb, he can immediately tell if the LAST switch is the correct switch or not. Supposing that it is not, then he has 3 switches to choose from. If the bulb were relatively cool, then it could be the first switch, if it were warm, it could be the second switch, and if it were hot then it would be the 3rd switch.
This works with 4 lightbulbs in that by flipping all 4 switches and then shutting them down at different times. Then, by entering the room, he is given time to feel the lightbulbs, judging by temperature, which order they were shut off and thus which switch they are connected to.

Very good Lifetime. [img]smile.gif[/img]

If we name the switches 1, 2, 3 and 4 he can flip switch 2 and keep it on for five or ten minutes. The he switches it off and flips switch 3 for five or ten minutes. Finally, he flips switch 4 and walks to the other room. If the light is burning, it was switch 4. If the lamp is hot, it was switch 3. If the lamp was a bit warmer than teh rest of the room, it was switch 2. If the lamp is just as warm as the rest of the room, switch 1 was the right switch.

Had a nightmare about lightbulbs,switches and spys.And when i woke up,i couldn't find the right switch for the lamp in my bedroom [img]smile.gif[/img]

Well Legolas,that was quite a difficult riddle,and i'm soooooo glad i know the answer now!There will be more riddles here,i'm sure.

bah **typical two fifty grumble** smartbuttness won't save ye from a gory death... [img]graemlins/firedevil.gif[/img]

I was right? :eek: Cool!

Anymore of these "riddles"? They're rather interesting when its rainy outside and theres nothing to do..

this is the first time i read this but if the bellhop takes one of the five and the cashier takes one of the five going back that leaves 3 dollars for all the salesmen together that means they each get one its not really a riddle just bad math by someone.

A little bit more correct solution to the lightbulb riddle:

1) Immediately turn on switches 1 and 2.
2) Wait for 25 minutes (or so).
3) Turn switch 2 OFF, and turn switch 3 ON.
4) Immediately go into the room with the light bulbs.

The bulb controlled by switch 1 will be on and hot, switch 2 will be off and hot, switch 3 will be on and cool, and switch 4 will be off and cool. This saves the spy from having to judge slight variations in temperature.

The 5-bulb riddle takes a lot more time:

1) Turn on switch 5.
2) Wait for 5 years.
3) Follow the previous list of instructions as described above. The bulbs controlled by switches 1-4 will be exactly the same, and the bulb controlled by switch 5 will be burned out.

Did we fry anybody's brains? [img]smile.gif[/img]

<blockquote>quote:</font><hr>
Originally posted by Legolas:
Warmer than you think.
<hr></blockquote>
LOL.

I got the riddle after the 'what else do lamps do hint', just in time to catch some choice phrasing by Legolas and SoS - Cheeky B$^"$%£$%s

Here's another one that's not so difficult, but sticks with the theme of captured spys;

The commandant of the camp is having a good week and captures 4 more spys. Again he gives them the chance to go free, if they can solve another of his fiendish puzzles, and they agree to give it a go.
All of the 4 are then buried up to their necks, one is outside the camp, facing the its outside wall. The other 3 are buried inside the camp in a line perpendicular to the the wall, again facing it (diagram below might help clear this up). As they can't move their heads round they can only see the spys directly infront of them. The commandant then brings out 4 hats, 2 blue and 2 red, and places them on the spys heads, in the order shown below;


The spys do not know the color of the hat on their own heads, and can only see the hats that are infront of them, (spy1 cannot see throught the wall though). The commandant says that if one of them can tell him the color of the hat on their head, without any communication between them, they can go free.

Which spy saves them?

I read this riddle in a book on myths and legends. Its pretty easy if you think about it for five seconds and it go's like this. What creature walks on four legs in the morning, two legs in the day and three legs at night?