HW for Monday

Use your data from class to calculate the index of refraction for the clear block of acryllic.  Answers will probably be around 1.5.  If you have data for water, calculate the index of refraction for it as well; that will be around 1.3 or so.

Here are some problems to try.  Use the following:

n = c/v

Snell's law:  n1 sin(theta 1) = n2 sin(theta 2), to solve.


1.  What is the index of refraction for a substance that slows light down to half its speed in a vacuum?

(2)

2.  What is the index of refraction for a substance that takes an initial light ray in air at 50 degrees (with respect to a normal line) and bends it to 34 degrees?

(1.37)

3.  A light ray hits a block of plexiglass (n = 1.65) at 45 degrees.  What is the angle of refraction inside the block?

(25.5 degrees)

4.  Thought questions.  Why do you suppose triangular prisms "break up" light into colors of the rainbow?  Would the same thing happen if a red laser entered a triangular prism in the same way?  Are post-rain rainbows a similar phenomenon?

From Pink Floyd: