In the diagram,the ray passing through the prism is parallel to the base. The refractive index of the material of the prism is:

$A$ light ray is incident on a prism at an angle of $45^o$ and produces minimum deviation. If the refractive index of the prism is $\sqrt{2}$,then the prism angle is .......... $^o$.

The angle of a prism is $A$ and one of its refracting surfaces is silvered. Light rays falling at an angle of incidence '$2A$' on the first surface return back through the same path after suffering reflection at the silvered surface. The refractive index of the material of the prism is

The figures represent three cases of a ray passing through a prism of angle $A$. The case corresponding to minimum deviation is

The principal section of a glass prism is an isosceles triangle $ABC$ with $AB = AC$. The face $AC$ is silvered. $A$ ray of light is incident normally on the face $AB$ and after two reflections, it emerges from the base $BC$ perpendicular to the base. The angle $BAC$ of the prism is: (in $^{\circ}$)

$A$ ray of light is incident at an angle of $60^o$ on one face of a prism of angle $30^o$. The ray emerging out of the prism makes an angle of $30^o$ with the incident ray. The emergent ray is