practice problems

1. Describe what happens to a light ray as it enters a piece of glass (or tank of water, for that matter) -

a. at a zero degree angle (with respect to the normal)

b. at a non-zero angle

(Though the math may be less comfortable to you, a relationship called Snell's law describes this all perfectly.)

2. Describe the law of reflection.

3. What exactly is the focal length of a lens or mirror? Under what circumstances are images formed AT the focal point?

4. Does a flat/plane mirror have a focal length? Discuss.

5. What is the difference between real and virtual images?

6. Draw what happens when several parallel rays of light hit:

a. convex lens

b. concave lens

c. concave mirror

d. convex mirror

e. plane mirror

7. "An image always forms at the focal length of a lens or mirror." This statement is false. Discuss.

8. A convex lens is similar to a _____. Why?

9. A concave lens is similar to a ______. Why?

10. With a convex lens, a real image is formed everywhere except when the object is located _____.

11. When you are using a magnifying glass or make-up/shaving mirror, where are you placing the object  to get a magnified image? What type of image is this?

12. What is nearsightness and farsightedness?  What types of lenses are used for nearsightness and farsightedness?

13.  What is interference of light?

14.  How is interference related to holography?