A ray of light is incident on an equilateral glass prism placed on a horizontal table. For minimum deviation which of the following is true ?

Question

G1 Physics · Accepted Answer

Derived solution: Step 1: For a prism use r₁ + r₂ = A and δ = i + e - A. At minimum deviation i = e and r₁ = r₂ = A/2, so μ = sin[(A + δₘ)/2]/sin(A/2). Step 2: Substitute the values given in the question and apply the geometry/sign convention shown. Step 3: On simplification the result is QR is horizontal. Therefore the correct option is B.