Clue to Riddle #7: Three Light Bulbs & Switches in a Room

7. A windowless room contains three identical light fixtures, each containing an identical light bulb or light globe. Each light is connected to one of three switches outside of the room. Each bulb is switched off at present. You are outside the room, and the door is closed. You have one, and only one, opportunity to flip any of the external switches. After this, you can go into the room and look at the lights, but you may not touch the switches again. How can you tell which switch goes to which light?
example of a three way switch
Light Bulbs or Light Globes get hot when they're on.

Have a play with the simulator below. Once you know what you're at don't forget to hide the bulbs whilst you're flicking the switches.
a bulb switched on a bulb switched off a bulb just switched off



Where next?
Questions Answer





© Nigel Coldwell 2004 -  – The questions on this site may be reproduced without further permission, I do not claim copyright over them. The answers are mine and may not be reproduced without my expressed prior consent. Please enquire using the link at the top of the page.
 


PayPal
I always think it's arrogant to add a donate button, but it has been requested. If I help you get a job though, you could buy me a pint! - nigel

This Website Uses Cookies

Mostly, but not entirely to remember if you have dismissed this very box. Also to increase the functionality of the site. The cookies I apply do not uniquely identify you, by continuing to use this site you agree to let me place a cookie. I also have advert and analytics providers, for more information click here here.x