campus Maths Puzzle

Q. There is a bulb inside the room and tree switches are out side the room. you have to find the switch connected to bulb by only once going inside the room.

Read Solution (Total 2)

Turn 1st light switch on, wait a few minutes, then turn it off and turn 2nd light switch on. Go into the room and feel the light bulbs. The one that's still warm is connected to the switch that you first turned on, the one that is on was the second switch you turned on, and the last bulb is controlled by the switch that you didn't touch.
12 years agoHelpfull: Yes(8) No(3)

switch on the first switch, let it be on for a while, now switch it off and switch on the 2nd switch go inside: if bulb is glowing-switch 2, if bulb is not glowing but hot-switch 1, if bulb is not glowing and not hot-switch 3
11 years agoHelpfull: Yes(3) No(0)

campus Other Question

Q. There is ten box having 10 balls in each of 10 gm of weight but however it come to know that one box among them has defective balls, all the ten balls are either 9 gm or 11 gm how to find that box. You can use digital balance and only taking one reading from it. Q. What is the sum of digits of Number obtain (10^3)^8-8.