$A$ thin prism of angle $15^o$ made of glass of refractive index $\mu_1 = 1.5$ is combined with another prism of glass of refractive index $\mu_2 = 1.75$. The combination of the prisms produces dispersion without deviation. The angle of the second prism should be ......$^o$

The diagram shows five isosceles right-angled prisms. $A$ light ray incident at $90^{\circ}$ at the first face emerges at the same angle with the normal from the last face. Which of the following relations will hold regarding the refractive indices?

In the diagram,a prism of angle $30^o$ is used. $A$ ray $PQ$ is incident as shown. An emergent ray $RS$ emerges perpendicular to the second face. The angle of deviation is.....$^o$

One face of a glass prism is silver-polished. $A$ light ray falls at an angle of $45^{\circ}$ on the other face. After refraction,it is subsequently reflected from the silvered face and then retraces its path. The refracting angle of the prism is $30^{\circ}$. The refractive index of the prism is:

The refracting angle of a prism is $A$ and the refractive index of the material of the prism is $\cot (A / 2)$. The angle of minimum deviation of the prism is

$A$ ray of light is incident normally on one of the faces of a prism of angle $30^\circ$ and refractive index $\sqrt{2}$. The angle of deviation will be.....$^\circ$