Find the value of angle of emergence from the prism. Refractive index of the glass is $\sqrt{3}$.

A ray enters normally at the first face ($i=0\Rightarrow r_1=0$).The angle of incidence at the second face $r_2=A=30^{\circ }$.Using Snell's Law at the second face:
$$\mu \sin r_2=1\sin e$$
$$\sqrt{3}\sin 30^{\circ }=\sin e$$
$$\sqrt{3}\times \frac{1}{2}=\sin e\Rightarrow \sin e=\frac{\sqrt{3}}{2}$$
$$e=60^{\circ }$$