7th Brain Teaser: 3 Lamps and 3 Switches

Interesting brain teaser presented by Serguei Vorojtsov. Subscribe to my newsletter at
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[simba00784]

this is a classic 'thinking outside the box question'.

you turn on one switch for a few minutes then turn it off. you then turn on the second switch. enter the room. the bulb which is hot but off is the first switch. the bulb which is on is the second switch. and the cold off bulb must therefore be the third

[fengineer08]

-Turn 1 switch on

-Leave 1 switch off

-Turn the last switch on for 2-3 minutes and turn it back off again.

-The switch you turned on will light up 1 bulb.

-The switch you left off will leave its bulb off.

-The switch you turned on for a few minutes will allow its bulb to heat up.

Go into the next room and check for the warm bulb.

Solved.

[H8tinVidz]

Its a little more complicated bcuz the switches can be in parallel in the circuit therefor# u can open all the lamps with 1 switch

[soursharpie]

cleverrrr. i was thinking way to simply... my initial guess was enter the room, leave the door open when you leave the room, and then you can see inside to tell which lamp corresponds to which lamp, but the real answer is much cleverer haha :)

[postnubilaphoebus96]

Figured it out in 30 seconds, easy, but nice :)

[thezimboman]

easy... turn on all 3 switches and you know they all light up a bulb!

[MrKoiking1]

look through the windowand go in after to watch tv in the light you just made.

[sonnycullen13]

Turn 1st on, wait. Turn 2nd on. Go in room. The third is the one that is off. The first is the one with the hot bulb. The second one is the one with the cold bulb.

[theburtonnn]

Use your shoe to prie open the door... the look inside at the light while you turn them on...

[yahoopig]

Get a fucking electrician

[bigfanowarriors]

turn 1 and 2 on

leave 3 OFF

turn 2 OFF

turn 1 OFF 15 minutes later

feel for the cold one = 3

feel the last two, HOTTER one = 1 and warm one = 2