Exercise 1


A light bundle going through the air makes an angle with the normal on a glass plate of 30°
The refractive index of the glass plate is 3/2 and the refractive index of air is 1. What is the angle made by the light bundle with the normal when it's in the glass plate?




Snell's law: ni * sin(oi) = nt * sin(ot)
  • ni = 1
  • oi = 30°
  • nt = 3/2
  • => (1)*sin(30°) = (3/2)*sin(ot)
    => (1/2) = (3/2)*sin(ot)
    => sin(ot) = (1/3)
    => ot = ASIN(1/3)
    => ot = 19.5°