Question

discuss normal and anomalous dispersion of light

Answer 1

Normal Dispersion: when the refractive index (n) of materials decreases with increasing wavelength ? of the light( case of visible light), this is known as normal dispersion, in this case, shorter wavelengths travel slower than longer wavelengths.

Anomalous Dispersion:  the medium is said to have anomalous dispersion if the index (n) increases with increasing wavelength ( the case in the ultraviolet). In this case, shorter wavelengths travel faster than longer wavelengths.