Changing the amounts of air and water in the bottles lets you change the pitch—how high or low the sound is. When you blow across the tops of the bottles, you're making the air inside vibrate. In bottles with more air, vibrations are slower, so the pitch is lower.
Answers & Comments
Answer:
Changing the amounts of air and water in the bottles lets you change the pitch—how high or low the sound is. When you blow across the tops of the bottles, you're making the air inside vibrate. In bottles with more air, vibrations are slower, so the pitch is lower.