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 ?

Question

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) Equal to 2 C (B) Less than 2 C (C) More than 2 C (D) None of the above

Tardigrade Admin · Accepted Answer

From ray diagram A=C+θ for TIR at A C θ > C so A > 2 C <img class="img-fluid question-image" alt="image" src="https://cdn.tardigrade.in/img/question/physics/27f0f8b61f9e93825346a1d202022940-.png" />

Q. 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 $C$ ?

Equal to 2 C

Less than 2 C

More than 2 C

None of the above

From ray diagram
$A = C + θ$ for TIR at $A C$
$θ > C$ so $A > 2 C$

Q. 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 ?