Question:

A monochromatic light is incident at a certain angle on an equilateral triangle prism and suffers minimum deviation. If the refractive index of the material of the prism is √3, then the angle of incidence is?

45o

90o

60o

30o

i = e; r1 = r2 = A/2 = 30°
By Snell's law
1 × sin i = √3 × sin(30°)
1 × sin i = √3 × (1/2)
sin i = √3 / 2
i = 60°