a. What is scattering of light? b. Explain Rayleigh scattering.
c. Why sky appears blue? d. Sky blue extends over a wide region. Why ?

Explanation

a. The irregular reflection of light in all direction at random from extremely small particles such as dust, molecules of air etc. is called scattering of light .
b. According to Rayleigh.s scattering law, the intensity of scattered light is inversely proportional to the fourth power of the wavelength.
i.e., Intensity, I `prop (1)/(lambda^(4))`
it is found tht shorter wavelengths are scattered more than longer wavelengths.
c. The blue colour of the sky is due to the scattering of light by small particles of the atmosphere. According to Rayleigh.s scattering law, the scattering ntensity is maximum for smaller wavelengths. the size of the particles in the upper atmosphere is smaller, so that the radiations of shorter wavelength are scattered with greater intensity. Sunlight is rich with blue and therefore the most intense scatted colour is blue. thus ksy appears blue.
d. scattering of upper atmospheric particles produces blue of the sky. Since the region of observation is extended the blue colours thus extends over a wide region.