Question

If the refractive indices of crown glass for red, yellow and violet colours are $1.5140$,$1.5170$ and $1.6434$,$1.6499$ and $1.6852$ respectively, then the dispersive power for crown and flint glass are respectively-

Answer 1

For crown glass:

$\omega =\frac{{\mu }_v-{\mu }_r}{{\mu }_y-1}=\frac{1.5318-1.5140}{1.5170-1}=0.034$

For flint glass:

$\omega =\frac{{\mu }_v-{\mu }_r}{{\mu }_y-1}=\frac{1.6852-1.6434}{1.6499-1}=0.064$