2007-01-19 04:07:04 · 13 answers · asked by dvdai14 2 in Science & Mathematics ➔ Physics
you mean that "does the speed of light change when going from in vacuum to another medium?, right?
Yes, the rate of change depends on which medium it is; however, the rate of change for light going from vacuum to our atmosphere, for example, is so small compare to how fast speed of light is, 3 * 10^8 [m/s], it'll become insignificant to our naked eyes.
2007-01-19 04:15:00 · answer #1 · answered by Cu Den 2 · 0⤊ 0⤋
The speed of light in a vacuum is an important physical constant denoted by the letter c for constant or the Latin word celeritas meaning "swiftness". It is the speed of all electromagnetic radiation in a vacuum, not just visible light.
In passing through materials, light is slowed to less than c by the ratio called the refractive index of the material. The speed of light in air is only slightly less than c. Denser media, such as water and glass, can slow light much more, to fractions such as ¾ and 2/3 of c. This reduction in speed is also responsible for bending of light at an interface between two materials with different indices, a phenomenon known as refraction.
Therefore the speed of light in vacuum us maximum. And what we know as "speed of light" is actual light;s speed while traveling through vacuum only.
2007-01-19 12:25:37 · answer #2 · answered by Anonymous · 0⤊ 0⤋
I read somewhere that if you had a purer vacuum, with less going on at the planck length you could artificially increase the speed of light - I realise it sounds far out and it may remain science fiction forever as the theories are untested - however the speed of light can be slowed down, its been slowed down to walking speed in labs only a few years ago shining through a Bose-Einstein condensate - whether it can be speeded up remains to be seen.
I read the idea in a book by Wil McCarthy - I believe it was 'collapsium'.
2007-01-19 12:16:05 · answer #3 · answered by Anonymous · 1⤊ 0⤋
Higher the refractive index lower the speed of light in that media. Speed of light in vacuum is maximum and it is the standard value that we refer to as the speed of light and therefore does not vary in vacuum.
2007-01-19 12:17:56 · answer #4 · answered by openpsychy 6 · 0⤊ 0⤋
Not that we know of.
A large amount of modern physics is based on the assumption that the speed of light in a vacuum is constant and all of experiments have been preformed to verify this assumption to a very high degree of accuracy.
That being said it could vary, but we know that if it does, then it varies extremely slowly.
2007-01-19 12:20:52 · answer #5 · answered by sparrowhawk 4 · 0⤊ 0⤋
The speed of light in a vacuum is the universal speed limit - nothing can go faster. It doesn't vary.
The speed of light in a medium is smaller than that of light in a vacuum, so something could go faster than light - in a medium.
2007-01-19 12:09:25 · answer #6 · answered by eri 7 · 1⤊ 1⤋
yes... in a vacuum, light is at its fastest. anything else can slow it down, but not by much. light is just another form of energy... think of heat. some materials transfer heat faster than others. its the same with light. and in a vacuum, light is travelling at its full speed.
2007-01-19 12:17:42 · answer #7 · answered by swatthefly 5 · 0⤊ 0⤋
may i know then how does speed of light becomes greater when going from medium to vacuum?
2014-06-25 06:37:55 · answer #8 · answered by Anonymous · 0⤊ 0⤋
As long as it's in a vacuum, there is no change. Going through any other substance, c is found by dividing by the index of refraction, eg,
Air---1.000294
Glass---1.46--1.96
Water---1.33
Diamond---2.417
2007-01-19 13:32:24 · answer #9 · answered by Steve 7 · 0⤊ 0⤋
No it's a fixed value and usually the number everone quioes. It's usually slower in other media like glass and water etc.
2007-01-19 12:10:31 · answer #10 · answered by Gene 7 · 0⤊ 1⤋