Riddle 5: Three Switches and a Lightbulb

Three switches and a lightbulb

 "Inside the room there is a lightbulb. Door that closes the room was sealed completely,. So there is no slot through which can be seen inside the room when the door is closed Outside the room there are three switches , but only one of them turns on the light bulb in the room, while the other two off. How would you do to determine which switch is the one that lights the bulb into the room only once ?.

SOLUTION:

To get to the solution of this great conundrum we must have in mind that a light bulb is heated, and the heat takes a while to dissipate when the light bulb goes off.

So, initially starting with three switches off, we can turn on the first switch for a few minutes. Then we turn it off, turn on the second switch and entered the room. If the bulb is on, then the second switch is that is connected to the bulb. If the room is turned off and the bulb is hot, the switch function will be the first switch . If the bulb is turned off and is not hot then the third switch is that switches the bulb.

  

What makes this particular conundrum, at least from my point of view, is that unlike others that the solution lies in pure logical reasoning or games hidden words in the title, presents us with a realistic situation, which we can implement and physically experience (preferably provided with a flashlight). In fact, it impels us to perform experiments with mind to finally reach a solution that is not a specific result, but an experimental method for information and discard possibilities by logical reasoning. 

When I heard for the first time this conundrum, more or less at age 8, I was caught between the switches and the room, which increasingly seemed darker; not come to solve it , I just gave up. However, hearing his explanation could almost feel mentally heat the bulb burning my fingertips, its light hitting in my eyes, and background logic of the problem, which seemed so palpable as the imagined bulb. It was an exciting experience and although there were countless subsequent experiences that led me to study physics, this was one of the earliest.

 Riddler 1 (variant):

Four switches and a lightbulb

"Inside the room there is a bulb La. Door that closes the room was sealed completely,. So there is no slot through which can be seen inside the room when the door is closed Outside the room there are four switches , but only one of them turns on the light bulb in the room, while the other three off. How would you do to determine which switch is the one that lights the bulb into the room only once ?.

SOLUTION:

To solve the conundrum variant with four switches assume that when the bulb lights up , it takes a while to warm up . We also assume, as in the previous case, if we turn off the lamp after lighting a while, the heat from the bulb takes a few minutes to dissipate. Thus, to determine which is connected to the bulb switch can proceed as follows. We turn on the first switch and waited long enough for the bulb to warm up in the event that that's the right switch. Then back to turn off the first switch and turn on the second. After waiting a few minutes we turn on the third switch without turning off the second, and walked quickly to the room. If the bulb is turned off and hot , the switch is searched first . If the bulb is lit and warm , the switch is the second . If the bulb is turned on and is not hot the switch is the third , and finally, if the bulb is turned off and is not hot , the switch will be the fourth .

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