question_answer

The critical angle between an equilateral prism and air is 45°. If the incident ray is perpendicular to the refracting surface, then                                                            [MP PMT 1986]

A)            After deviation it will emerge from the second refracting surface

B)            It is totally reflected on the second surface and emerges out perpendicularly from third surface in air

C)            It is totally reflected from the second and third refracting surfaces and finally emerges out from the first surface

D)            It is totally reflected from all the three sides of prism and never emerges out

Correct Answer: B

Solution :