Homework (C)

Have a go at these problems:

1. What is the index of refraction of a substance that reduces the speed of light to 75% of its value in a vacuum?

2. What is the speed of light in water (n = 1.33)?

3. A light ray enters a piece of plastic at an angle of 60 degrees (with respect to the normal line). It is refracted to an angle of 40 degrees. What is the index of refraction of the plastic? Assume that the index of refraction of air is 1.

4. Can an index of refraction be less than one?

5. What are the units of index of refraction?

6*. A light ray hits a piece of quartz (index of refraction = 1.46) at an angle of 30 degrees (with respect to normal). What is the angle of refraction inside the quartz? (Hint: Solve for the sine of the angle, and then take the 'inverse sine' on your calculator. That would be the 2nd SIN key.)

7. What is atmospheric refraction?

8*. How do prisms break up white light into colors?

* tricky