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Assume you have hooked up a video camera to a TV so that if you aim the camera at something, it will show up on the TV. Assume you aim the camera right at the TV What will appear in the TV?
Hint
The message from the camera to TV is not instant.Answer
You will see whatever was on the TV before you aimed the camera at it, surrounded by an image of the TV's border. There will be several of them inside each other.Hide Hint Show Hint Hide Answer Show Answer
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I forgot to add to the answer "Because no matter how fast the signal is, it is not instatanious.
How interesting would it be to watch this in slow motion?! I think TV cameras take pictures at 30 frames per second (I'm not sure) and if you had a huge TV, you could watch the frames being built up. Or maybe you could do this with a web cam? They have a lower refresh rate? (But a lower resolution)
Interesting anyway
Interesting anyway
It is like placing two mirrors facing each other. Whatever is inbetween them is transposed infinitely in each mirror, growing more and more distant until you cannot even see it. The concept is the same. And the frame rate wouldn't do a bit of good. You're dealing with the speed of light here. Meter/nanosecond. It would instantly appear to be infinite images.
That last comment is absolutely incorrect. The frame rate does slow things down.. it is true that you are dealing with the speed of light (2.99E8m/s or 0.299 m/ns), but depending how fast the electronics involved are, a significant bottleneck does build up.. Try it with a webcam and your pc monitor sometime, if you don't believe me (and are prepared to be mesmerized and lose hours or days when you could be doing something else...)
when i did this, i had two lights on and i basically saw a blue screen with a whole bunch of tv's and the two light's production.
Aug 14, 2002
Very interesting theoretical answer, but nothing can substitute actual experimental evidence. In practice, the frame of the tv screen will appaear for a while with a blue or white blob in the center. It's the video equivalent of feedback, thus and since white is a combination of all the colors in the visual spectrum, it is prduced when the video is looped just like the audio gets louder and louder in a feedback loop. Blue is just the source's misrepresentation of white, or the camrea's off-balance
100% origional!
Wow, I wondered about this several times long before I found this. I came up with an answer, which I now know is correct.
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