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A man paints with his brains and not with his hands. ..."Michelangelo (1475-1564, Italian sculptor, painter, architect and poet)"
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Author Topic: Speed of Light question  (Read 6179 times)
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PanicAttack
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on: September 12, 2009, 04:21:02 pm » posted from:Singapore,,Singapore

Hi,

I'm new here and I have a question that has been bothering me for a long time - I just couldn't get the answer.

If a car is driving at the speed of light and switches on its head-lights, what will happen?  Will the head-light still be able to "light" the areas in front?
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Fu-Kwun Hwang
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Reply #1 on: September 12, 2009, 09:29:32 pm » posted from:Taipei,T\'ai-pei,Taiwan

According to special relativity: There is no way a car (any object with rest mass which is not zero) can reach speed of light in vacuum c.
However, particle can be accelerated to very closer to speed of light.

If a small object being accelerated near speed of light, for example: 0.9c (where c is the speed of light in vacuum), and the object switch on a head light.

Because light need to be reflected to be seen.
The object might be able to see light reflected from some distance within small angle.
The angle will be smaller if the speed is closer to speed of light.
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FGZstar
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Reply #2 on: October 27, 2009, 05:38:38 pm » posted from:Napier,Hawke's Bay,New Zealand

One thing which has always puzzled me about this is if, theoretically, an object were to travel at the speed of light, would it become invisible?
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dwiphy
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Reply #3 on: March 29, 2010, 10:58:36 am » posted from:Melbourne,Victoria,Australia

Invisible or unseen by human eyes?
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Fu-Kwun Hwang
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Reply #4 on: March 29, 2010, 11:42:49 am » posted from:Taipei,T\'ai-pei,Taiwan

One thing which has always puzzled me about this is if, theoretically, an object were to travel at the speed of light, would it become invisible?
To the driver: the time is freezed.
However, to other people, if the light enter my eye then I will see it. If it is not entering my eye, I would not be able to see it.

At night, the sun still emitting light to the sky. However, teh sky is dark because those ray moving away from us and it did not enter our eye.
Light has to enter our eye to be seen!
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A man paints with his brains and not with his hands. ..."Michelangelo (1475-1564, Italian sculptor, painter, architect and poet)"
 
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