Question

Light enters water from air at an angle of 25° with the normal, Θ1. If water has an index of refraction of 1.33, determine Θ2.

A) 18.5°
B) 34.2°
C) 31.8°
D) 71.5°

Answer 1

By Snell's law:

η = sini / sinr. i = 25, η = 1.33

1.33 = sin25° / sinr

sinr = sin25° / 1.33 = 0.4226/1.33 = 0.3177 Use a calculator.

r = sin⁻¹(0.3177)

r ≈ 18.52°

Option A.

God's grace.