Why sky is blue?

The sky appears blue to most people because light from the sun is scattered in all directions by the gases and particles in the Earth's atmosphere. When sunlight hits the atmosphere, it is made up of a spectrum of colors, with shorter wavelengths (like blue and violet light) on one end and longer wavelengths (like red and orange light) on the other.

When sunlight encounters molecules in the Earth's atmosphere, such as oxygen and nitrogen, some of the light is scattered in different directions. This process is called Rayleigh scattering, and it is caused by the way that light interacts with particles that are much smaller than its wavelength.

The shorter wavelengths of light, like blue and violet, are more easily scattered in all directions by the atmosphere. This means that when sunlight reaches the Earth's surface, there is a greater concentration of blue and violet light in the sky than other colors. As a result, the sky appears blue to most people.

There are also other factors that can affect the color of the sky, such as the presence of clouds or pollutants, which can scatter light differently and cause the sky to appear other colors. However, in general, the sky appears blue to most people because of the way that sunlight is scattered by the Earth's atmosphere.
So now you now why sky is blue.

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