Question

why sky appear in blue colour during day time

Answer 1

The blue of the sky is the result of the diffusion of sunlight through the atmosphere. If it did not exist, one would see a celestial vault all black and the stars would be visible in broad daylight.

The white light of the Sun is a mixture of all the colors of the rainbow. The light travels in the form of waves of different lengths. Each color has its own wavelength. The light travels in a straight line until it encounters an obstacle that returns it in another direction. When the sun's rays enter the atmosphere, they encounter atoms, air molecules, drops of water and the dust from which the atmosphere is formed. The air molecules have the right size to diffuse the shortest wavelengths of light, purple, indigo and blue in this case; The longer wavelengths, such as the red ones, are scarcely diffused by these air molecules.


It is therefore a mixture of violet, indigo, blue, green and a small fraction of the other colors that are diffused throughout the sky, conferring this blue which is well known.

Answer 2

hey sistah,
 it is because molecule in the air scatter blue light frm the sun more than they scatter red light. when we look towards the sun at sun set we see red and orange colour becauze the blue light has been scattered  out away frm the line of sight.

i hope this much helps u..