$A$ light wave has a frequency of $4 \times 10^{14} \,Hz$ and a wavelength of $5 \times 10^{-7} \,m$ in a medium. The refractive index of the medium is

$A$ ray of light is incident at an angle $i$ on a glass slab of refractive index $\mu$. The angle between the reflected and refracted light is $90^{\circ}$. Then, the relationship between $i$ and $\mu$ is

In a medium,the speed of a light wave decreases to $0.2$ times its speed in free space. The ratio of relative permittivity to the refractive index of the medium is $x: 1$. The value of $x$ is $...........$ (Given: speed of light in free space $= 3 \times 10^8 \ m \ s^{-1}$ and for the given medium $\mu_r = 1$)

The bottom of a container filled with liquid appears slightly raised because of

State Snell's law of refraction.

If the angle of incidence is twice the angle of refraction in a medium of refractive index $\mu$,then the angle of incidence is