Question

A narrow beam of light is travelling through a transparent liquid. It meets the surface as shown, at
an angle of incidence of 40°. The refractive index of the liquid is 1.5.
What is the angle of refraction as the light enters the air?
A 25° B 27° C 60° D 75°

Answer 1

60°

Explanation:

the angle incidence of 40° and the refractive index of the liquid is 1.5 ,so we multiply the angle incidence and the refractive index so we get the answer is 60°

Answer 2

Answer:

D 75°

Explanation:

Snell's law states that n = sin r/sin i (for scenarios in which the light is traveling from a more dense medium to a less dense medium)

n = refractive index : 1.5

sin r = sin angle of refraction

sin i = sin angle of incidence

1.5 = sin r/sin 40

sin r = 1.5 * sin(40)

r = sin-1 (1.5 * sin(40) )

= 74.6(1 d.p) or 75