The critical angle for refraction from glass to air is 30° and that from water to air is 37°. Find the critical angle…..

Q. The critical angle for refraction from glass to air is 30° and that from water to air is 37°. Find the critical angle for refraction from glass to water

(a)sin-1(5/6)

(b) 51°3′

(c) 61°2′

(d) 63°3′

Ans: A

Refraction from glass to air , critical angle = 30°

μg sin30° = μa sin90°

Refraction from water to air , critical angle = 37°

μw sin37° = μa sin90°

Let critical angle for Refraction from glass to water = θ

sinθ = sin30°/sin37° = (1/2)/(3/5) =5/6

θ = sin−1(5/6)

Leave a Comment