The velocity of light in glass having a refractive index of $1.5$ is $2 \times 10^8 \ m/s$. What is the refractive index of a liquid in which the velocity of light is $2.50 \times 10^8 \ m/s$?

The difference of speed of light in the two media $A$ and $B$ $(v_{A}-v_{B})$ is $2.6 \times 10^{7} \, m/s$. If the refractive index of medium $B$ is $1.47$,then the ratio of refractive index of medium $B$ to medium $A$ is: (Given: speed of light in vacuum $c = 3 \times 10^{8} \, m/s$)

The length of a vertical pole at the surface of a lake of water $\left(\mu = \frac{4}{3}\right)$ is $24 \, cm$. Then,to an underwater fish just below the water surface,the tip of the pole appears to be ......... $cm$ above the surface.

$A$ concave mirror is placed on a horizontal surface and two thin uniform layers of different transparent liquids (which do not mix or interact) are formed on the reflecting surface. The refractive indices of the upper and lower liquids are $\mu_1$ and $\mu_2$ respectively. The bright point source at a height $d$ ($d$ is very large in comparison to the thickness of the film) above the mirror coincides with its own final image. The radius of curvature of the reflecting surface is

$A$ ray of light is incident upon an air/water interface (it passes from air into water) at an angle of $45^o$. Which of the following quantities change as the light enters the water?
$(I)$ wavelength
$(II)$ frequency
$(III)$ speed of propagation
$(IV)$ direction of propagation

$A$ ray of light is incident on a medium of refractive index $\mu$ at an angle of incidence $i$. On refraction in the medium,$\delta$ is the angle of deviation. Then: