Saturday, February 27, 2010

Is snow clear, and the only reason we see it as white is due to the refraction of light?

The snow is reflecting the light, not refracting. The difference being that the light doesn't get split up into different colours. If you look at water at a very slight angle it can appear white for the same reason, but yo'd be looking at light reflecting off the surface, not refacting, which involves passing through the water.





When light passes from 1 medium to another it refracts, which means a bends a bit. Different wavelenghts of light (different colours) bend to a greater or lesser degree, so the different colours split.





In snow the light gets bounced around in billions of different directions, so it appears white from any angle. In glacial snow you get ground up rock and other particles trapped in the snow. This refacts the light and it splits, with blue light tending to get bent the most, hence glacial snow appear blue. Same affect of particles in the atmosphere make the sky look blue - bends more, and the sunset look red as red light goes strighter (you look towards the sun to see a red sunset, but at 90 degrees to the sun to see the blueist skys)Is snow clear, and the only reason we see it as white is due to the refraction of light?
More reflection than refraction. We see the reflected light as being white. But why? The answer lies in an effect called mie scattering. The small snow crystals, and the surfaces of the crystals first absorb the light, then re-emit it in all directions ('scattering'). Because the crystals are much larger than the wavelength of visible light, the light is reflected back at all wavelengths, so we see the snow as white. If the light passes through (as in a clear solid block of ice), we see the ice as being transparent, because there is no mie scattering.Is snow clear, and the only reason we see it as white is due to the refraction of light?
If you shine a green light on snow the reflected light will be green. If you shine sunlight (a mixture of all colors ... that can be separated in a rainbow) you will see reflected white light. Snow reflects all photons while a pure black surface will absorb all photons and none are available for you to see. Snow is a form of ice which is clear on a lake or pond but looks white as snow because the snow crystals (six-pointed and none alike) can individually reflect light rather than let the light pass through unchanged (like ice and clear glass).
snow appears white due to total internal reflection caused to to lots of air pockets in it(change in medium ice to air) .while ice is clear (mostly) due to relative lack of air bubbles . the same thing happens when we see a bubble under water and a a certain angle of vision it appers to shine like a mirror this is due to fact tht there is a change in medium water to air (denser to rarer)
Although the ice is clear, scattering of light by the crystal facets and hollows/imperfections mean that the crystals often appear white in colour due to diffuse reflection of all spectrum of light by the small ice particles.
You are in-fact right. Think of it like this snow is ice and usually ice is clear however when you chip ice it turns white because light can no longer perfectly travel through it. This works with snow if snow was perfect it would be clear.
It's white. Just like for example a sheet of white paper.





White things are white because they reflect the whole spectrum of visible light.
That is so, or so I believe.
everything you see around you is to do with refraction of light, like the sea although its clear it apears blue
no its definitely white until it melts in your hand then its clear





hope this helps xoxo
Supposedly so
You could apply that to anything- all colours are just refraction of light. snow is white.
  • Ltd
  • No comments:

    Post a Comment