Find the value of the angle of emergence from the prism. Refractive index of the glass is 1.732.

(1) 60°                                  (2) 30°

(3) 45°                                  (4) 90°

Solution: Answer (1)

From the ray diagram shown in the figure, we can say that

r1 + r2 = A = 30°

r2 = 30° (r1 = 0°)

From Snell’s law,

√3sinr2 = 1 x sine

√3sin30° = sine e = 60°