Brain Teasers
Light Bulb Flipping
Assume you have a switch to a light bulb. It starts out off. After half a minute, you flip the switch. After a quarter of a minute you flip the switch again. And do so after an eighth, a sixteenth, and a thirty-second, and so on. At the end of the minute, is the bulb on or off?
Hint
There could be three answers here.Answer
There are three answers depending on how you think about it.1) I never said the switch was flipped again, so it would be on.
2) No Light bulb could go that fast so most likely it would be burned out.
3) You can't answer this because the light switch would be flipped infinitely many times before the minute was over. And infinity isn't odd or even.
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Comments
I really like the question. I don't believe your going to burn out the bulb, however, the human reflex usually cannot react faster than 0.1 seconds. At some point you will lag the required switch point until you'll just keep moving the switch until time expires. The position it ends up in depends on your reaction time. If you discount physics and think just about the math then there is no answer, because of the infinite issue. Good job.
I have puzzles like this before. If you are walking from A to B, you first have to pass the halfway point. When you are at the halfway point, in order to get to B you must pass the halfway point between there and B. If you continue like this, you will never get anywhere.
Very nice, but kinda confusing.
You blew it dude....if you are doing an inverted square of a second, then you aren't getting any closer to a second everytime you divide it. A quarter is LESS than a half, as is an eighth, as is a sixteenth...(enter the runner's paradox). Hence, you are jumping to half of a second and working backwards. I think you may want to reword this question. Good idea though...
I don't understand the first answer...can anyone explain it to me?
The sum of an infinite series can be a finite number. Thus, 1/2 + 1/4 + 1/8 + ... = 1
I thought 2.
At my apartment, it would be out. If I flip a light bulb on and off that fast, the voltage spikes blow it!. I had to convert all my bulbs to flourescent.
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