Question

If their is a bulb in the 2 flor and u r in the 1th flor and their is 3 switch and u have to tell which one is the switch of bulb and u can only go once at the 2nd flor

Answer 1

Switch on switches 1 & 2, wait a moment and switch off number 2.

• Enter the room. Whichever bulb is on is wired to switch 1, whichever is off and hot is wired to switch number 2, and the third is wired to switch 3.