Bulbs

This is one of my most favorite logic puzzles.
Imagine you are in a room with 3 switches. In adjacent room there are 3 bulbs (all are off at the
moment), each switch belongs to some bulb. It is impossible to see from one room to another. How
can you find out, which switch belongs to which bulb, if you may enter the room with bulbs only
once?

3 Answers

62
Lokesh Verma ·

This was one of the fist to be asked here :)

23
qwerty ·

a vry old question ...u check it by touching the bulbs .....
first on a switch ......wait for 5 minutes ...turn of that switch and turn on a nother switch and go inside the room .....
now the bulb that belongs to d first speech will b hot and off...the one belonging to 2nd switch will be on ..and the remaining bulb will be of the last switch

24
eureka123 ·

yeah ..very easy....9th grader question

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