One Bulb with 3 Switches
You have 3 switches in a room. One of them is for a bulb in next room. You can not see whether the bulb is on or off, until you enter the room. What is the minimum number of times you need to go in to the room to determine which switch corresponds to the bulb in next room.
the answer will be 1.
we have to go to that room only once.
Steps:
First switch on the first switch, keep it on for say 2-3 minutes.
then switch of first switch and on the second switch.
as soon as u on the second switch go to the room.
If you found that the bulb is glowing that means the second switch corresponds to the room.
if not then touch the bulb if it is warm that means it corresponds to the second switch if not then it corresponds to the third switch.
The answer is 1.
here is the details:
S1,S2,S3
Switch ON all 3 switches one by one. dont visit the room as bulb will be glowing for sure.
Then, Switch OFF S3, check bulb on or off, If OFF, then Minimum visit=1;
else
Switch OFF S2 leaving S3 in OFF, check bulb on or off, If OFF, then visit=2;
else
Then, Switch OFF S1 leaving S3,S2 off, check bulb on or off, If OFF, then visit=3;
\Hence ,
Minimum visit=1 and maximum vist=3
Minimum visit=1 and Maximum vist=2
On Switch A and check (visit one )
if bulb is on then Switch a is bulb switch if not
Turn off A and turn on B, go to room and check (second visit)
if bulb is on the switch B is bulb switch , else switch C
Minimum visit=1 and Maximum vist=2
On Switch A and check (visit one )
if bulb is on then Switch a is bulb switch if not
Turn off A and turn on B, go to room and check (second visit)
if bulb is on the switch B is bulb switch , else switch C
1 just get good at guessing nerd or just flick all the switches on
Your Answer
More puzzles to try-
I can be cracked Riddle
I can be made. I can be cracked. I can be told. I can be played. Who am I?Read More »A man with a car riddle
A man with a car on his head is called…….Read More »My first in camel riddle
My first is in camel and in hamster. My second is in otter but not in ferret. My third is ...Read More »Not alive
It has a long neck, A name of a bird, Feeds on cargo of ships, It’s not alive, What is ...Read More »Knight on a Chess Board
Given the size of the chess board and initial position of the knight, what is the probability that after k ...Read More »Why blonde cannot dial 911?
Why blonde cannot dial 911?Read More »Count the number of squares
Can you count the number of squares in the figure below?Read More »Poor and King
The cost of making only the maker knows, Valueless if bought, but sometimes traded. A poor man may give one ...Read More »Evil Joju riddle
Jacob, his daughter, and the evil Joju lived in a city. Jacob was in debt to Joju, and Joju had ...Read More »Beginning of end riddle
I am the beginning of end, I am the fifth of my family, I appear twice in a week but ...Read More »How many did you count?
This is a simple one. You just have to count the number of F in the given sentence. Finished Files ...Read More »Floating up and down
I come to you round, Floating up, floating down, A single pop, I am on the ground, Then comes your ...Read More »Overweight Ball
There are 8 identical balls. In that one of the ball is overweight. There are only two chances to weigh ...Read More »We clap for it
It is an object, everywhere it goes people clap for it. What is it?Read More »Very Exciting
It is very interesting and knowledgeable. Its front is very eye catching but its inside tells all. What is it?Read More »Find the Day
On a new year day, two old friends John and Jacob meet at a party. As they met after a ...Read More »MatchSticks Squares Riddle
You need to move three matchsticks to form three squares. Can you do it?Read More »Is the square in the middle a perfect square?
Is the square in the middle a perfect square? Although it is a perfect square, the sides may appear to ...Read More »Brightens your day
What brightens your day when it is dark, although it is usually in the shade?Read More »Find my encrypted message
I am in a situation and sent you a letter as below, Decode the cipher rebus puzzle and find my ...Read More »
