If a friend throws a ball at 20km/h, to you, the spectator, the ball appears to be traveling at 20km/h, right? Well, if your friend walks forward at 5km/h, and throws the ball at 20km/h, to you, the standing spectator, the ball seems to travel at 25 km/h, right?
Does the same apply to the speed of light? If you shot a laser pointer in a vacuum, and moved forward, would the light move faster than normal?
I don't know if it would move faster, or if the beam of light would just become more powerful... What do you think?
2007-01-26 13:29:56 · 7 answers · asked by theVisionary 4 in Science & Mathematics ➔ Physics
In fact, the speed of light coming out of the laser does increase is the source is moving, nor does it get stronger in any way. There is a set of equations called Maxwell's equations, and their solution shows that the speed of light never changes, no matter what.
All of this is also supported by experiment. Under no circumstances will light ever speed up.
You may ask, well how can that be possible. This definately screws up a bunch of physical concepts.
A man named Albert Einstein asked the same question you did. He thought about it hard and long. To answer how this peculiar property of light could be true, he created the Special Theory of Relativity. All relativity phenomena such as length contraction and time dilation all come from the fact that the speed of light never changes, no matter what referene frame you are in.
2007-01-26 13:43:51 · answer #1 · answered by Tony O 2 · 1⤊ 0⤋
The speed of light remains exactly the same for all observers - regardless of their velocity. This is the main difference between classical (Newton) and relativity (Einstein).
If a source of light (a star, for instance) were to travel toward the earth at the speed of light, the resulting energy of that light would instantly vaporize anything in its path.
Not very intuitive - but true, none the less.
2007-01-26 13:40:56 · answer #2 · answered by LeAnne 7 · 0⤊ 1⤋
Einstein wondered about the same questions as you do and came to the conclusion that the speed of light is constant irrespective of the speed of the source. Einstein did thought experiments and you appear to be doing the same thing, such thinking should be encouraged.
2007-01-30 12:12:01 · answer #3 · answered by lester_day 2 · 0⤊ 0⤋
An observer who's stationary relative to you would see your laser light the same colour as you see it. If you then started to move towards them they would see the light change colour - it would become more blue. Its the same Doppler effect that changes the pitch of a police siren as it passes you, but you would need to be moving at a substantial fraction of the speed of light before you noticed any colour change.
2007-01-26 23:00:55 · answer #4 · answered by black sheep 2 · 0⤊ 0⤋
The first calculation is incorrect. But to calculate the speed, is very complicatet!
light has no airresistance, therefore speed of light is the same in vacuum or not.
2007-01-26 13:44:11 · answer #5 · answered by Anonymous · 0⤊ 1⤋
The speed of light is independant of the speed of its source. Period!
2007-01-26 13:41:54 · answer #6 · answered by Chug-a-Lug 7 · 0⤊ 0⤋
That question was answered by Einstein in 1905:
http://en.wikipedia.org/wiki/Special_relativity#Causality_and_prohibition_of_motion_faster_than_light
2007-01-26 14:02:51 · answer #7 · answered by arbiter007 6 · 0⤊ 0⤋