Finding Switch for the Bulb in the next room

A bulb in the next room

Naman is told that there are 3 switches in a room, and one of them is assigned to a bulb in the next room. Below are the premise, rule, and objective for the given puzzle. Read them carefully and find out the solution for the same.

Premise – There are 3 switches in a room, where one of them is assigned to a bulb which is placed in another room.

Rule – You can’t see whether the bulb is on or off until you leave the room.

Objective – find the minimum number of times you need to go to the next room to identify which switch corresponds to the bulb in the other room.

Finding switch for the bulb in next room
Finding switch for the bulb in next room

A bulb in the next room

Naman is told that there are 3 switches in a room, and one of them is assigned to a bulb in the next room. Below are the premise, rule, and objective for the given puzzle. Read them carefully and find out the solution for the same.

Premise – There are 3 switches in a room, where one of them is assigned to a bulb which is placed in another room.

Rule – You can’t see whether the bulb is on or off until you leave the room.

Objective – find the minimum number of times you need to go to the next room to identify which switch corresponds to the bulb in the other room.

 Solution for the switch of the Bulb:

As we know the rule and objective for this puzzle we can achieve our aim by following the below steps:-

  • Firstly, you have to initially turn on the first switch and keep it on for 2-3 minutes.
  • Next, turn off the first switch and turn on the second one.
  • Go and check to the other room as soon as you turn on the second switch.
  • If the bulb is glowing, the second switch corresponds to the light bulb.
  • However, if the bulb doesn’t glow, but it feels warm on touching, then it is clear that the first switch was assigned to the bulb.

If in case it is neither lit nor warm, then the third switch is the desired switch. Therefore, you need to go to the other room only once to find out which one is the accurate switch.

Bulb in the next room

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