In refraction,light waves are bent on passing from one medium to the second medium,because,in the second medium

The ratio of the thickness of plates of two transparent mediums $A$ and $B$ is $6 : 4$. If light takes equal time in passing through them,then the refractive index of $B$ with respect to $A$ will be:

If $_i{\mu _j}$ represents the refractive index when a light ray goes from medium $i$ to medium $j,$ then the product $_2{\mu _1} \times {\,_3}{\mu _2} \times {\,_4}{\mu _3}$ is equal to

The speed of light in air is $3 \times 10^8 \, m/s$. What will be its speed in diamond,whose refractive index is $2.4$?

$A$ 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

An infinitely long cylinder of radius $R$ is made of an unusual exotic material with refractive index $-1$ (See figure). The cylinder is placed between two planes whose normals are along the $y$-direction. The center of the cylinder $O$ lies along the $y$-axis. $A$ narrow laser beam is directed along the $y$-direction from the lower plate. The laser source is at a horizontal distance $x$ from the diameter in the $y$-direction. Find the range of $x$ such that light emitted from the lower plane does not reach the upper plane.