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.
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
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
Your Answer
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