Refraction from denser to rarer medium for a light ray, the value of angle of refraction at the condition of critical angle is :

What is the relation between the refractive index of water with respect to air $\left({}_{a }\mu _w\right)$, and the refractive index of air with respect to water $\left({}_{w }\mu _a\right)$.

If the refractive index of water with respect to air (${}_{a }\mu _w$)  is $\frac{5}{3}$.  Calculate the refractive index of air with respect to water (${}_{w }\mu _a$).

In the given ray diagram correct relation for Snell's law is

Light enters from air to glass plate having $1.50$ refractive index. What is the speed of light in glass? (Given-speed of light in vacuum $3\times {10}^8 \mathrm{m} {\mathrm{s}}^{-1}$)

The refractive index of medium $B$ with respect to medium $A$ in the given figure is given by

Light enters from air to kerosene having refractive index of $1.47$. What is the speed of light in kerosene, if the speed of light in air is $3\times {10}^8 \mathrm{m} {\mathrm{s}}^{-1}$?

Figure shows a ray of light as it travels from medium 1 to medium 2. If refractive index of medium 1 with respect to medium 2 is $\frac{\sqrt{2}}{\sqrt{3}}$ then the value of angle x is