$A$ plot between the angle of deviation and angle of incidence is shown in the figure. From the graph,one can say that the prism angle is ....... (in $^{\circ}$)

$A$ ray of light is incident on the first face of an equilateral glass prism at an angle of incidence '$i$'. The emergent ray just grazes along the adjacent face. The refractive index of the prism is $\sqrt{2}$. The value of the angle of incidence at the first face is $(\sin 45^{\circ} = 1/\sqrt{2}, \sin 90^{\circ} = 1)$.

$A$ ray of light suffers a minimum deviation when incident on an equilateral prism of refractive index $ \sqrt{2} $. The angle of incidence is (in $^{\circ}$)

$A$ ray of light is incident at an angle '$i$' on one face of a prism of small angle '$A$' and emerges normally from the other surface. If '$\mu$' is the refractive index of the material of the prism,then the angle of incidence is:

The angles of incidence and emergence of a light ray passing through a prism of angle $A$ are $i$ and $e$ respectively. The total deviation produced by the prism is

In the given figure,the face $AC$ of the equilateral prism is immersed in a liquid of refractive index $n$. For an incident angle of $60^{\circ}$ at the side $AC$,the refracted light beam just grazes along the face $AC$. The refractive index of the liquid is $n = \frac{\sqrt{x}}{4}$. The value of $x$ is (Given refractive index of glass $= 1.5$)