EPT"if a car is travelling at the speed of light, and while travelling, turns it's head lights on, what happens?"
thought experiment
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nimysa
United States383 Posts
"if a car is travelling at the speed of light, and while travelling, turns it's head lights on, what happens?" | ||
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Symmetry
Canada294 Posts
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micronesia
United States24483 Posts
Your time would dilate in order to make up for the apparent discrepancy an outside observer would see. edit: I took the question to mean your car was moving at ALMOST the speed of light so it would make sense. | ||
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Severedevil
United States4820 Posts
Anyways, I think the light appears to be moving at the speed of light from the perspective of a viewer in the car (as Micronesia said) as well as from a stationary perspective, but time is different from the perspective of the car as from the perspective of a stationary viewer. (Hence the slower aging for people going near the speed of light.) | ||
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Murlox
France1699 Posts
edit : and yeah, car is a massive object. | ||
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Rev0lution
United States1805 Posts
What happens is so broad a question that you can really answer it in many ways. 1) The car remains the same at constant speed. 2) In the point of view of a bystander who could see the car moving at the speed of light would not see the light emiting from the car if standing on its side. Since the car and the light are traveling at the same speed the shining of the light would be diminished so low that you could not notice it. 3) Standing in front of the car you would see a ray of light passing you by. etc. Another reason the light can't project itself outside of the car is because it would mean that the light of the car is traveling faster than the car itself. Since nothing can travel faster than the speed of light. You'd probably not see light coming from the car if you were looking at it pass you by. you -> looking at this direction car -^ lights going that way. | ||
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sigma_x
Australia285 Posts
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vAltyR
United States581 Posts
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Sky
Jordan812 Posts
Public Science Papers Many research papers have other ideas that weren't touched upon included in the "limitations" or "conclusions" section. The drawback being that there are a lot of terms that have complex meanings. At least you have that quality of dwelling on something unknown to you. + Show Spoiler + Always favored Feynman over Einstein... Feynman was a PLAYA!!! | ||
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Pawsom
United States928 Posts
On September 02 2009 10:20 Murlox wrote: SC2 beta key for the driver. Haha  | ||
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theonemephisto
United States409 Posts
From the perspective of the DRIVER, the light would zoom ahead of you at the speed of light. From the perspective of the BYSTANDER, the light would still be moving at the speed of light, just as fast as the car is. Which is impossible. Which is why it's theoretically impossible to go the speed of light. Now if the car was moving at ALMOST the speed of light, time would dilate for the car, making the speed of the headlight seem the same from both perspectives. | ||
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KwarK
United States41567 Posts
On September 02 2009 10:31 vAltyR wrote: Relativity is awesome. We usually think of time and distance as constant, whereas speed is changing depending on both time and distance. In actuality, it's the other way around. Speed remains constant, and time and distance is what changes to keep it constant. I very much dislike this. It makes my brain hurt to think about just how far I'm moving when you take the expansion of the universe and the whirling of galaxies into account. | ||
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ghostWriter
United States3302 Posts
On September 02 2009 11:01 Kwark wrote: I very much dislike this. It makes my brain hurt to think about just how far I'm moving when you take the expansion of the universe and the whirling of galaxies into account. Have you ever seen the pictures where they compare the sizes of the earth to jupiter/the sun then the solar system to the largest stars ever discovered? This is seriously mindblowing. | ||
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citi.zen
2509 Posts
+ Show Spoiler + v = (w - u)/(1 - wu/c2), where u = c | ||
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Dasher
United States71 Posts
On September 02 2009 10:18 Symmetry wrote: Light travels at the same speed from all frames of reference. Not true! http://en.wikipedia.org/wiki/Slow_light | ||
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micronesia
United States24483 Posts
On September 02 2009 12:14 citi.zen wrote: Technically the answer is indeterminate, since the relative velocity formula contains a 0/0. + Show Spoiler + v = (w - u)/(1 - wu/c2), where u = c First of all that's no surprise since a massive object can't travel at the speed of light anyway (hence my claim that we should assume the car is moving very close to the speed of light). Second of all I don't believe you can use that formula for photons. | ||
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CharlieMurphy
United States22895 Posts
A better way to think of it is if you take a ray of light and assume that it can shoot off another ray of light. But since they both move the same speed it would just be a brighter ray, not a longer ray. | ||
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micronesia
United States24483 Posts
On September 02 2009 14:40 CharlieMurphy wrote: the most basic answer would be the lights go on but don't seem to shine anywhere. A better way to think of it is if you take a ray of light and assume that it can shoot off another ray of light. But since they both move the same speed it would just be a brighter ray, not a longer ray. This is the second time tonight I am speechless. | ||
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Nitrogen
United States5345 Posts
On September 02 2009 14:57 micronesia wrote: This is the second time tonight I am speechless. LOL. | ||
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