If the refractive indices of a prism for red,yellow,and violet colours are $1.61$,$1.63$,and $1.65$ respectively,then the dispersive power of the prism will be:

Mention the constituent colors of white light.

Compare the dispersive powers of two prisms if one of them deviates the blue and red rays through $10^{\circ}$ and $6^{\circ}$ respectively,and the second prism through $8^{\circ}$ and $4.5^{\circ}$.

Let us list some of the factors,which could possibly influence the speed of wave propagation:
$(i)$ nature of the source.
$(ii)$ direction of propagation.
$(iii)$ motion of the source and/or observer.
$(iv)$ wavelength.
$(v)$ intensity of the wave.
On which of these factors,if any,does
$(a)$ the speed of light in vacuum,
$(b)$ the speed of light in a medium (say,glass or water),depend?

The dispersive power is maximum for the material

Explain dispersive and non-dispersive medium.