A light beam strikes a piece of glass at a 60.00° incident angle. The beam contains two wavelengths, 450.0 nm and 700.1 nm, for which the index of refraction of the glass is 1.4824 and 1.4750, respectively. What is the angle between the two refracted beams?

2 answers

You don't need the information regarding the wavelengths.

Step 1: Use Snell's law twice (once on each of the two rays) to find the angle each is refracting at. I'll call the first ray A and the second ray B.

Snell's Law: n1*sin(theta1) = n2*sin(theta2)

First Snell's for A:
n1 = 0 (air)
theta1 = 60 degrees
n2 = 1.4824
theta2A = ??? degrees

Second Snell's for B:
n1 = 0 (air)
theta1 = 60 degrees
n2 = 1.4750
theta2B = ??? degrees

Step 2:Subtract the smaller angle from the larger angle to find the angle between the two refracted rays.

|theta2A - theta2B| = Answer.
Required