| A | B |
|---|
| pitch | How high or low a sound is |
| compressed | Molecules that are squeezed together |
| medium | Matter that carries sound waves |
| decibels | The volume of a sound is measured in these units |
| echo | A sound that bounces off a surface |
| vibration | A back and forth movement of matter |
| volume | The loudness of a sound |
| frequency | The number of vibrations per second |
