Puzzle

[Mjolinor]

There?s a standard filament-type light bulb in a closed room upstairs. It is controlled by one of three standard on-off switches that are all turned off, downstairs.
You are downstairs.
How can you discover for certain which switch controls the light by operating one or more switches and then taking only one trip upstairs into the closed room?

[xant14]

turn two on, check the light, if its still off, you know it the third switch.
If it is still off, it one or the other of the switches 1 and 2... pull the fuse. Dunno... or do i.

[Bulld0g]

turn two on, check the light, if its still off, you know it the third switch.
If it is still off, it one or the other of the switches 1 and 2... pull the fuse. Dunno... or do i.

Owwww me head. send someone up to check whilst you wait downstairs

[on_the_jazz]

Turn on switch one. Then turn it off after 1 minute.
Turn on switch two.
Go upstairs. If the bulb is on then its switch 2. If its warm to the touch its switch 1. If its cold its switch 3.

[chroma]

240v buzzer + bayonet/ edison screw fitting
Or a bayonet/es extension cord.

[forntida]

Turn on switch one. Then turn it off after 1 minute.
Turn on switch two.
Go upstairs. If the bulb is on then its switch 2. If its warm to the touch its switch 1. If its cold its switch 3.

That is the correct logical answer. There are two or three illogical answers;

You could go outside and look up at the window and check if the light was on. You could do Bulldogs solution, etc.

Then agai if the light happens to fuse when you switch it on the whole thing is up in the air.

I'm just trying to confuse everybody because I had to get up early because of Man Cold and Lainie was not online to nurse me.

[zaphodbb]

leave the cupboard door open and all the other doors open upstairs switch all the lights off, close all the curtains and stand at the bottom off the stairs turn each one on and look up the stairs when you see the light you will know. failing that take a hostage, put all the switches in the on position lock the hostage in the cupboard then turn each switch off, when you hear a scream you will know thats the switch. ah just figured it out !!

[Evastar]

The other two switches probably control lights that you can see, i.e. the landing light and the hall light, or the light to the room you are in. So if you turn on one and you don't see anything light up, that's the closed room.