What Causes the Colors in Soap Bubbles?

[physgrl]

Homework Statement

1. A soap bubble is colored because of:

a. dispersion
b. diffraction
c. thin film interference
d. all of the above

Homework Equations

The Attempt at a Solution

I don't understand the concepts very well...at first I though the answer was dispersion thinking it worked as a prism but the correct answer is supposed to be thin film interference.
can someone explain to me the concept? (also I don't understand refraction very well either)

thanks in advance!

 

[collinsmark]

You might want to try this:

http://www.lmgtfy.com/?q=thin+film+interference