Sunday, February 7, 2010

So: Where Does The White Go When The Snow Melts?

Disappearing White of Snow

Question - Where does the white go when snow melts? ----------------- Snow is frozen water in many little crystals. It is frozen water just like ice cubes are frozen water, except snow is not in a block shape, but in many little crystals.

The reason snow looks white to you is because when the colors in the light touch it the snow does not absorb any of them, so to your eyes, because it did not absorb, it looks white.

When the snow melts it means the little tiny water crystals are melting, just like an ice cube melts when it gets warm. All the snow turns into water and makes the ground wet. Now the snow no longer exists, so the light does not have any more snow to touch anymore, therefore you do not see white any longer. Instead, you see the color of whatever object was under the snow (like the grass). Grace Fields


Joe, Here is something to try: get a cube of ice and - very carefully - scrape off a few ice shavings. Do the shavings look white? Now take the shavings into your palm and squeeze hard so that the shavings merge together - if you do this right, the merged shavings will look clear again. What do you think is happening?

You might also consider why it is that a drop of water on the kitchen counter top will look transparent, but when a paper towel is placed on it, the paper towel gets dark. Why should a clear liquid make a dark spot on a paper towel? This has everything to do with the way light interacts with matter, and how the size of the object controls how much light is absorbed or reflected. Greg (Roberto Gregorius) ================================================

When snow melts, the white goes the same place that the light goes when you turn off a light bulb. It goes away. Michael Loop ====================================================
Snow is white because the flakes are the right size to scatter visible light that reflects off them. In contrast an ice cube (especially when wet) is still the same "stuff" -- water but it is transparent to visible light.

The "white" of the snow goes away because the flakes melt and stick together in large clumps that can no longer scatter the light. By the way light scattering is what happens when light that reflects off of a surface, reflects back in all directions about the same amount. This is different than a mirror where the light reflecting off the mirror reflects back at the same angle at which it strikes the mirror. Vince Calder ================================================

White is the color made by lots of little surfaces, like the glitter of broken glass. When a glass chunk is whole, it is clear like water, like melted snow. Then when you grind it into sand, it's white.

This time you have made white! And when snow melts, yes, whiteness is destroyed . White is just the color of scrambled light, bounced around until it is dizzy, by lots of little partial mirrors.

It is 100% reflection, but scrambled so you do not get the picture images you can see in a nice large mirror. By partial mirror, I mean the way you can see yourself in a window sometimes.

Windows are about 92% clear + 4% mirror on the front + 4% mirror on the back. Having two different mirrors makes the reflection a bit blurry sometimes. If you ground this window up to a powder, it would be a pile of white powder. There is almost no such thing as a clear powder. (PS-do not try that. Glass dust is very dangerous.)


1 comment:

jmmb said...

That question sure brings back memories! Try asking a young child where the white goes. The answers are priceless.