Question

During the day time the sky is blue due to the scattering of light. Light reaching in a room also scatters light. But no blue colour is seen. Why?

Answer 1

Hint :We know that we can see various different colors due to the wavelength of each color. Each color has a specific wavelength. Each wavelength activates different cells in the retinas. These wavelengths are scattered as they travel a long distance through the atmosphere.

Complete Step By Step Answer:
The reason for the blue colour of the sky is attributed to the phenomenon of scattering of light by the particles of the atmosphere. This can be visualized by an example that a normal glass jar does not take up much space, but if it falls to the ground and breaks, small glass pieces get scattered everywhere and effectively cover a large area on the ground.
The atmosphere of the earth has a lot of small particles including water droplets and dust particles. These small particles absorb light radiation and re-emit them in all directions. Thus, effectively deviating the radiation from its straight path and scattering it. This phenomenon is known as the scattering of light. Rayleigh's law of scattering states that the amount of scattering of radiation by particles in its path depends upon the inverse of the fourth power of the wavelength.
Scattering of light is the phenomenon in which light rays get deviated from its straight path on striking an obstacle like dust or gas molecules, water vapors, etc. Sunlight reaches Earth’s atmosphere and is scattered in all directions by all the gases and particles in the air. Blue light is scattered more than the other colors because it travels as shorter, smaller waves. This is why we see a blue sky most of the time.

Note :
Remember that this question could also have been framed in the way that, ‘Why does outer space look black while our sky looks blue?’ This has essentially the same answer because outer space does not have a thick atmosphere containing many particles that can scatter light in the way the atmosphere of the earth does.