$A$ glass prism of refractive index $1.5$ is immersed in water (refractive index $4/3$). $A$ light beam incident normally on the face $AB$ is totally reflected to reach the face $BC$ if

Consider a glass prism immersed in a liquid as shown below. The refractive index of glass and liquid is $1.5$ and $1.2$, respectively. $A$ ray of light enters the prism perpendicular to the face $AB$. If the ray is totally internally reflected at the face $AC$, then the largest value of angle $\theta$ is:

$A$ transparent solid cylindrical rod has a refractive index of $\frac{2}{\sqrt{3}}$. It is surrounded by air. $A$ light ray is incident at the mid-point of one end of the rod as shown in the figure. The incident angle $\theta$ for which the light ray grazes along the wall of the rod is

If the critical angle for total internal reflection from a medium to vacuum is $30^o$,the velocity of light in the medium is

Let the refractive index of a denser medium with respect to a rarer medium be $n_{12}$ and its critical angle be $\theta_C$. At an angle of incidence $A$ when light is travelling from a denser medium to a rarer medium,a part of the light is reflected and the rest is refracted,and the angle between the reflected and refracted rays is $90^o$. Angle $A$ is given by

If a ray of light in a denser medium strikes a rarer medium at an angle of incidence $i$,the angles of reflection and refraction are $r$ and $r^{\prime}$ respectively. If the reflected and refracted rays are at right angles to each other,the critical angle for the given pair of media is