Question

A cubic zirconia is submerged in oil. A light ray enters one face of the zirconia crystal, then travels at an angle of 35° with respect to the normal. What was the ray's angle of incidence on the zirconia crystal with respect to the face of the crystal? Express your answer in degree (Use "degree" as the unit).

Answer 1

Here, this question falls under Snell's law or law of refraction here according to the question there are two mediums one is Oil and another one is Cubic Zirconia crystal the diagram is shown below.

Here, medium 1 (OIL) refractive index(n1) is 1.46 and angle of incidence(?1) is we have to find

medium 2(Crystal) refractive index (n2) is 2.18 and angle of incidence (?2) is 35 degree.

As per snell's law- n1sin?1=n2sin?2 or n1/n2=sin?2/sin?1....................(1)

Inserting all values in Eq 1

sin?1=(n2/n1)*sin?2

sin?1= (2.18/1.46)*sin(35)

?1=sin^-1(0.85)= 58°

So, angle of ray's incidence on crystal wrt to the face of the crystal is 58°