I STRONGLY recomend you visit this webpage for a deeper understanding of sound waves.
You can also watch any of the videos below:
Okay, so Bill Nye isn't exactly the most sophisticated or perfect way to learn something, but it helped in elementary and middle school, didn't it? Work with me here, it's about baby steps, and you've already suffered through the videos from the last chapter that were much more intense.
12.1 Sound waves
12.2 Sound intensity and resonance
Sound interactive
12.3 Harmonics
Chapter homework:
8 thru 16;
17 thru 23;
28 thru 35.