White light is incident on the interface of glass and air as shown in the figure. If only green light undergoes total internal reflection,then the rays in the air are:

The critical angle for light going from medium $A$ into medium $B$ is $\theta$. The speed of light in medium $A$ is $V_A$. What is the speed of light in medium $B$?

$A$ ray of light from a denser medium strikes a rarer medium. The angle of reflection is $r$ and that of refraction is $r'$. The reflected and refracted rays make an angle of $90^{\circ}$ with each other. The critical angle will be

$A$ point source of light $S$ is placed at the bottom of a vessel containing a liquid of refractive index $\mu = 5/3$. $A$ person is viewing the source from above the surface. There is an opaque disc $D$ of radius $r = 1\, cm$ floating on the surface of the liquid. The centre of the disc lies vertically above the source $S$. The liquid from the vessel is gradually drained out through a tap. The maximum height $h$ of the liquid for which the source cannot be seen at all from above is: (in $, cm$)

Consider the ray diagram for the refraction given below. The maximum value of angle $\theta$ for which the light suffers total internal reflection at the vertical surface is:

Brilliance of diamond is due to