| A | B |
|---|
| speed of sound varies from one another | medium |
| how high or low a sound seems to be | pitch |
| units for expressing frequency | Hertz |
| sounds with 120 of these units can be painful | decibels |
| causes a sound in front of a moving sound source to seem to have a higher pitch and frequency | Dopple effect |
| sounds that have a frequency too high for people to hear | ultrasonic |
| a measure of how well a sound can be heard | loudness |
| used to graph representations of sound wave | oscilloscope |
| represented by the troughs on a graph from an oscilloscope | rarefactions |
| When it is larger, the sound is louder. | amplitude |
