Question

The refractive index of glass with respect to air is $\frac{3}{2}$. The refractive index of air with respect to glass will be?

Answer 1

If the refractive index of glass with respect to air is $\frac{3}{2}$, the refractive index of air with respect to glass will be $\frac{2}{3}$

$n_{21}$ = $\frac{1}{n_{12}}$