For an equilateral prism,the angle of incidence and the angle of emergence are each equal to $3/4$ of the prism angle. The angle of deviation is .......... $^o$.

$A$ ray of monochromatic light is passing through an equilateral prism $(ABC)$ as shown in the figure. The refracted ray $(QR)$ is parallel to its base $(BC)$ and the angle of incidence $(i)$ is $50^\circ$. Then the angle of deviation $(\delta)$ is: (in $^\circ$)

Assertion: There exist two angles of incidence for the same magnitude of deviation (except for minimum deviation) by a prism kept in air.
Reason: In a prism kept in air,a ray is incident on the first surface and emerges out of the second surface. If another ray is incident on the second surface along the path of the previous emergent ray,then this ray emerges out of the first surface along the path of the previous incident ray. This principle is called the principle of reversibility of light.

$A$ monochromatic ray of light is incident normally on a thin prism of refracting angle $A$. The ray is deviated through an angle $(1.15)^{\circ}$ in passing through the prism. The ray reflected internally from the second face emerges from the first face making an angle of $(6.3)^{\circ}$ with the incident ray. The refractive index of the prism is

The expected graphical representation of the variation of angle of deviation $\delta$ with angle of incidence $i$ in a prism is:

$A$ ray of light is incident on an equilateral glass prism placed on a horizontal table. For minimum deviation,which of the following is true?