Question

A ray of light $\left(GH\right)$ is incident on the glass-water interface $DC$ at an angle $i$. It emerges in air along the water air interface $EF$ (see figure). If the refractive index of water ${\mu }_w$ is $4/3$, the refractive index of glass ${\mu }_g$ is

• A. $\left(3/4\sin i\right)$
• B. $1/\sin i$
• C. $\left(4\sin i/3\right)$
• D. $\left(4/3\sin i\right)$

Answer 1

The correct option is B $1/\sin i$

for Air$-$ water interface

$\theta ={\sin }^{-1}\frac{3}{4}$

for glass water interface

$\frac{\frac{4}{3}}{\mu }=\frac{\sin i}{\frac{3}{4}}\mu =\frac{1}{\sin i}$