What is dispersion of light? Explain it with a diagram. Also explain the cause of dispersion.

Explanation

Dispersion of light:

Cauyse of dispersion: If `lamda` is the wavelength of light and `mu` is the refractive index of the material of prism for a particular wavelength, then according to Cauchy.s formula.
`mu=A+B/(lamda^(2))+C/(lamda^(4))`, where A,B, and C are constants.
When angle of prism (A) is small, then angle of deviation `sigma=A(mu-1)`.
Since `lamda_(v)ltlamda(R)` so `mu_(V)gtmu_(K)`. Hence `delta_(V)gtdelta_(R)`.
`:.` Violet colour deviates maximum and the red colour deviates minimum. Since the wavelength of other colours lie in between that of red and violet, therefore the other colours will deviate in between red and violet. In this way all the colours will get separated from each other.