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pivoxa15
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Ice cubes do not have a colour but snow (which is claimed to be frozen water or ice) is white. Why?
"claimed to be" ? Do you doubt that? Have you ever carried a handful of snow into the house? What happened?pivoxa15 said:Ice cubes do not have a colour but snow (which is claimed to be frozen water or ice) is white. Why?
White is not a color. So snow doesn't have a color either.pivoxa15 said:Ice cubes do not have a colour but snow (which is claimed to be frozen water or ice) is white. Why?
Because she makes the dwarves shower first.Why is snow white?
HallsofIvy said:"claimed to be" ? Do you doubt that? Have you ever carried a handful of snow into the house? What happened?
lalbatros said:Snow crystals have many facettes.
Each facette reflect a small part of the light.
An ice cube basically shows two facettes. You can observe easily that each do reflect some light.
Consider now the same volume of ice. The physical properties are the same (refractive index is the same) but you have maybe millions of facettes and the reflection is then a million times larger. The reflexion can become so large that in the end snow looses transparency and attenuate light quite a lot. The theory is a little bit more complicated because of multiple reflexions and attenuation, but the principles remain.
Another effect of the powder structure of ice is the diffusion of light.
You can observe the same effect on any transparent material, like glass or even sand.
Crush it fine and it will look whiter and brighter. Whitheness and brightness is something to be discussed also in more detail: take a book on color perception or colorimetry.
White cement (prepared with whiter raw materials) appears brighter when it is grinded finer.
Michel
cyrusabdollahi said:Haven't you seen the inside of a freezer?
The answer is in post#4 of the Physics FAQ (particularly in the moral at the end).pivoxa15 said:Ice cubes do not have a colour but snow (which is claimed to be frozen water or ice) is white. Why?
Gokul43201 said:The answer is in post#4 of the Physics FAQ (particularly in the moral at the end).
pivoxa15 said:Could you give me a link to it?
lalbatros said:Snow crystals have many facettes.
Each facette reflect a small part of the light.
An ice cube basically shows two facettes. You can observe easily that each do reflect some light.
Consider now the same volume of ice. The physical properties are the same (refractive index is the same) but you have maybe millions of facettes and the reflection is then a million times larger. The reflexion can become so large that in the end snow looses transparency and attenuate light quite a lot. The theory is a little bit more complicated because of multiple reflexions and attenuation, but the principles remain.
Another effect of the powder structure of ice is the diffusion of light.
You can observe the same effect on any transparent material, like glass or even sand.
Crush it fine and it will look whiter and brighter. Whitheness and brightness is something to be discussed also in more detail: take a book on color perception or colorimetry.
White cement (prepared with whiter raw materials) appears brighter when it is grinded finer.
Michel
Sure, you could rearrange the crystal structure by releasing and reforming the bonds that hold the water molecules in place.pivoxa15 said:Could you take a little bit of snow and make it so it has the physical features of ice again i.e. become more transparent?
russ_watters said:Sure, you could rearrange the crystal structure by releasing and reforming the bonds that hold the water molecules in place.
In other words, melt it and re-freeze it.
Absolutely. When it forms in the atmosphere, it is suspended in the air.pivoxa15 said:You would assume that the way water was fozen in the atomsphere is different to the re-freeze (i.e. done in the fridge)? Hence get different structures the second time round (i.e. more ordered structures).
Farsight said:White is not a color.
Snow appears white because it reflects all colors of the visible spectrum. This means that when sunlight or artificial light hits a snowflake, it bounces off and reflects back to our eyes as white light, making the snow appear white.
Technically, snow is not completely colorless. Snowflakes are actually made up of water molecules that have a slight blue tint, but when light is reflected off of them, the combination of all colors creates the appearance of white.
The color of snow can change based on certain factors such as pollution, dust, and temperature. Pollution and dust particles can get trapped in snow, giving it a gray or dirty appearance. Temperature can also affect the color of snow, as warmer temperatures can cause the snow to melt and refreeze, altering its appearance.
Under certain lighting conditions, snow can appear to have a blue or pink tint. This is due to a phenomenon called "albedo," where the color of an object is affected by the color of the light source. When snow is illuminated by a blue or pink light source, it can take on those colors.
Studying the color of snow and ice can give us insights into various natural processes and phenomena, such as the effects of pollution and climate change on the environment. Additionally, understanding the science behind color in ice can help us develop new technologies and materials, as well as improve our understanding of light and color in general.