The curve of angle of incidence versus angle of deviation shown has been plotted for a prism. The value of the refractive index of the prism used is:

$A$ ray of light suffers minimum deviation when incident on a prism having an angle of the prism equal to $60^{\circ}$. The refractive index of the prism material is $\sqrt{2}$. The angle of incidence (in degrees) is . . . . . . .

If the refractive index of a material of an equilateral prism is $\sqrt{3}$,then the angle of minimum deviation of the prism is......$^o$

The critical angle between an equilateral prism and air is $45^o$. If the incident ray is perpendicular to the refracting surface,then

$A$ 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

Angle of minimum deviation is equal to the half of the angle of prism in an equilateral prism. The refractive index of the prism is . . . . . . .