There are 3 bulbs(B1, B2 and B3) in a room on 1st floor, they can be operated using 3 switches(S1, S2, S3) present on the ground floor. You don’t know which Switch is for which bulb. How can you figure out, which switch is for which bulb if you are allowed to visit 1st floor only once.
Think before you give up, its really possible.
See Solution : 3 bulbs and 3 switches
Assuming all switches are turned off initially, You can do the following:-
1.) Turn on switch S1 for 5 minutes.
2.) Turn Off switch S1.
3.) Turn on switch S2.
4.) Go Upstairs.
5.) Glowing bulb can be assigned to Switch S2.
6.) Touch both other bulbs, hotter one should be assigned to switch S1 and the other one to switch S3.
1.) Turn on switch S1 for 5 minutes.
2.) Turn Off switch S1.
3.) Turn on switch S2.
4.) Go Upstairs.
5.) Glowing bulb can be assigned to Switch S2.
6.) Touch both other bulbs, hotter one should be assigned to switch S1 and the other one to switch S3.
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you have to firstly swicth-on 1 bulb for 15 minutes. after swith off it.. then again switch 2 bulb then go into the room and find that – o1 bulb have HOT (15 minutes), 2nd is (Which is already on) & third one is remaining (which is Cold – neither on or off). – GOT It 🙂
S its rgt
I thought of a solution of removing 1 bulb from its socket and checking rest in 1 visit.
@e32d1c88f429c2a64731e40db681407e:disqus but you have to go up only once, so that wont work