question_answer

A light ray is incident by grazing, one of the face of a prism and after refraction ray does not emerge out, what should be the angle of prism while critical angle is C?

A)  \[A>2C\]                            

B)  \[A<2C\]

C)  \[A=2C\]                            

D)  None of these

Correct Answer: A

Solution :

                From figure, \[A=C+\theta \] For total internal reflection at AC \[\theta >C\] So,          \[A>2C\]