Why is the Sky Blue and What Causes This Color?

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The sky appears blue due to the scattering of sunlight by gases and particles in the atmosphere, with blue light being scattered more than other colors because of its shorter wavelength. This phenomenon is explained by Rayleigh's scattering law, which states that scattering is inversely proportional to the fourth power of the wavelength. As a result, violet light is scattered the most, but blue is more visible to the human eye. The sky's color can appear lighter near the horizon due to atmospheric density changes. Additionally, the discussion touches on the intrinsic blue color of pure water, which is a separate but related topic.
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hi ,
please tell me why sky is blue?
 
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wasi-uz-zaman said:
hi ,
please tell me why sky is blue?

Sunlight is scattered by gases and particles in the atmosphere. Blue light is essentially a shorter, smaller wave, and is therefore typically more scattered than the other colors.

If you look more closely, you'd see its not REALLY "blue". Its bluer straight up, but gets lighter and whiter towards the horizon, etc.

This is related to why water can look blue too.
 
If you Google "why sky is blue" you get 786,000,000 hits. The first page is all remarkably good. If there is something you still don't understand after reading that, you might post a specific question here.
 
Tea Jay said:
This is related to why water can look blue too.

not quite. Pure water appears blue because it is intrinsically blue.
 
wasi-uz-zaman said:
hi ,
please tell me why sky is blue?

No, not in general but at times , yes... The law is Raleigh's Scattering law.
Scattering \propto1/λ4

As wavelength increases scattering decreases.
Wavelength increases as we go from right to left of the word : VIBGYOR

We know that the density of atmosphere decreases as we go up higher and higher. By Raleigh's scattering law the diameter of the particle must be greater than the wavelength of a particular colour. So violet is scattered the most in upper region of atmosphere and red the least in lower region. This is why we see somewhat orange colour in atmosphere at times of dusk mainly ( and little at dawn). The blue colour is scattered at upper regions mainly because of shorter wavelength because light is both wave like and particulate. The particulate size of blue is less.
 
Bloodthunder said:
not quite. Pure water appears blue because it is intrinsically blue.

You are saying that distilled water is blue? I don't believe that.
 
phinds said:
You are saying that distilled water is blue? I don't believe that.

http://en.m.wikipedia.org/wiki/Color_of_water
 
Bloodthunder said:
http://en.m.wikipedia.org/wiki/Color_of_water[/QUOTE]

Very interesting. Thanks for that. I was glad to see that my eyes were not deceiving me on small quantities, but I see that you are fundamentally right (assuming, as one always must assume, that the wiki is right --- but in this case iit SOUNDS right)
 
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