>>>>>In one room, there are three switches. They control three lightbulbs in an adjoining room, but you don't know which switch controls which lightbulb. All switches are initially in the "off" position. You can't see the other room from where the switches are.
>>>>>
>>>>>Your task is to find out which switch controls which lightbulb. You can manipulate the switches all you want, and then go ONCE into the adjoining room to inspect the lightbulbs.
>>>>
>>>>
>>>>Hmm.. Flip the first switch and leave it on for 60 seconds. Turn it off and flip the 2nd.
>>>>Go into the room, note which light is on, feel for the hot bulb and you'd know which switches control which lights.
>>>
>>>Yes, that is the correct solution.
>>
>>But the setup is obsolete. All my bulbs are cold. I didn't even think of hot bulbs.
>
>I always wonder what kids must think when their parents say "Oh look, there's a choo-choo". No kid today has seen (well, 99.9%) a steam engine in operation.
>Same for the telephone "ringing".

And most toy trains (esp wooden), and the symbol for a train is still a steam loco, even though most kids born over the last few decades will only see such in museums, Thomas the Tank Engine and old Westerns.

Similarly, the symbol for a speed camera on the roads is an old bellows contraption (not even a classic SLR), whicj most people will never see in their lives.

In a simialr vein, it strikes me as strange the "De Yoot'" don't question some of the antiquated expressions we use in everyday speech:

"Hang up" the phone. ???? "My phone you press a red button!"

"Turn over" the TV channel (from the days when you turned a dial) ???? "My telly you hit buttons on the remote"

And in my house, I still prefer to extoll the kids to "pull the chain" after them, rather than "crank the handle" :-)
I know most people would probably say "Make sure you flush it" so mine often mix the two and say "flush the chain" lol