vels from rarer to denser material. how is this possible.
2006-09-27 03:52:12 · 7 answers · asked by Anonymous in Science & Mathematics ➔ Physics
The *maximum* speed of light IS a constant. That doesn't mean that light always travels that fast, it means it's a speed limit. There are lots of ways to slow light down...but no way to speed it up above the top limit. That top limit is a constant that's used in many other forumulas, where it's used as a constant.
Make sense?
2006-09-27 03:56:37 · answer #1 · answered by Anonymous · 1⤊ 0⤋
The speed of light through space is constant, and in a straight line.
Matter distorts space in such a way that light bends when it gets near matter. The light is still travelling in a straight line, but the space it traverses is curved.
Inside a transparent medium, like glass, the light must follow a path so curved that even though it is travelling at C, it takes longer to traverse than is does in air, which in turn is a longer path than through a vacuum.
Two little demonstrations.
1. look across the edge of a sharp knife at a regularly patterned area. You will see the pattern distort along the edge of the knife.
2. look through a feldspar crystal at some printing, the image doubles because the structure of the crystal creates TWO paths for the light.
2006-09-28 05:52:51 · answer #2 · answered by disco legend zeke 4 · 0⤊ 0⤋
It's not. Light waves traveling through dense dust will be deflected. Only the longer wavelengths will stand a better chance of passing through.This changes the red shift and our perception of the sources distance.The speed remains constant.
2006-09-27 11:03:27 · answer #3 · answered by S.A.M. Gunner 7212 6 · 0⤊ 0⤋
You need to read the fine print. Light moves at velocity "c" in a vacuum. Moves slower in optical glass. In fact different frequencies of light have different velocities when moving through glass and this is why white light can be separated by a prism.
2006-09-27 11:10:17 · answer #4 · answered by Anonymous · 1⤊ 0⤋
Well it takes a million years for a photon to get from the suns core to the surface and only 8 minutes to get to earth.
2006-09-27 10:56:05 · answer #5 · answered by David W 1 · 0⤊ 0⤋
The 'speed of light' is max speed in a vacuum.
2006-09-27 11:00:11 · answer #6 · answered by Carter S 2 · 1⤊ 0⤋
this is because it is being obstructed by the particles, gases etc in the atmosphere and refraction may also cause this
2006-09-27 10:56:22 · answer #7 · answered by mr crazy 2 · 0⤊ 0⤋