How can you determine which switch is connected to which bulb if you are only allowed to enter the room once.
Three switches outside a windowless room.
The warmer of the two.
Turn the first two switches on and leave them on for 2 minutes.
Then switch on the second switch and enter the room.
Then switch on the second switch and enter the room.
Feel the two bulbs that are not lit.
Switch on the first switch leave it for a minute and then switch it off again.
A windowless room contains three identical light fixtures each containing an identical light bulb or light globe.
Switch on the first switch leave it for a minute and then switch it off again.
You are outside the room and the door is closed.
Each bulb is switched off at present.
Then turn the second switch off and enter the room after half a minute.
The second switch will be connected to the light that is on the first switch will be connected to the light with the warm bulb and the third switch.