$A$ ray of light is incident on a transparent sphere at an angle of $\pi / 4$ and is refracted at an angle $r$. The ray emerges from the sphere after suffering one internal reflection. The total angle of deviation of the ray is

The angle of incidence is found to be twice the angle of refraction when a ray of light passes from vacuum into a medium of refractive index $\mu$. The angle of incidence will be

Calculate the value of $n_{32} \times n_{21} = .... $

$A$ ray of light is incident at an angle of $75^{\circ}$ into a medium having refractive index $\mu$. The reflected and the refracted rays are found to suffer equal deviations in opposite directions. The value of $\mu$ is:

$A$ light of wavelength $600 \ nm$ in air enters a medium of refractive index $1.5$. Inside the medium :

$A$ light of wavelength $\lambda_{1}$ and velocity $C_{1}$ travels from the first medium of refractive index $\mu_{1}$ into the second medium of refractive index $\mu_{2}$. The wavelength and velocity of light in the second medium are $\lambda_{2}$ and $C_{2}$ respectively. The refractive index of the second medium with respect to the first medium is given by: