Question

There are 3 switches on the ground floor of a building. Every switch has a bulb corresponding to it. One bulb in on the ground floor, the other on the 1st floor and the third bulb is on the second floor. You cannot see any of the bulbs from the switchyard and neither are you allowed to come back to the switchyard once you check the bulbs. How will you find that which bulb is for which switch?

Answer 1

There are many ways actually.....
- Switch on all the 3 bulbs at the same time.
- After 5 min switch off any one switch i.e. switch A . After 10 min switch off the second switch i. e. switch B After 15 min switch off the third switch i. e switch C
- Check the bulbs
- 1 bulb should be hot second will be hotter third will be hottest
- it shows that switch A belongs to the first bulb switch B belongs to the second bulb switch C belongs to the third bulb
...
hope it helps
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