| A | B |
|---|
| wave | A disturbance that transmits energy through matter or space. |
| medium | A substance through which a wave can travel. |
| pitch | How high or low a sound is perceived to be. |
| infrasonic | The term describing sounds with frequencies lower than 20 Hz. |
| ultrasonic | The term describing sounds with frequencies higher than 20,000 Hz. |
| Doppler effect | The apparent change in the frequency of a sound caused by the motion of either the listener or the source of the sound (refers to sound only). |
| loudness | How loud or soft a sound is perceived to be. |
| noise | Any undesired sound, especially nonmusical sound, that includes a random mix of pitches. |
| echo | A reflected sound wave. |
| interference | A wave interaction that occurs when two or more waves overlap. |
| diffraction | The bending of waves around a barrier or through an opening. |
| reflection | When a wave bounces off of the |
| density | mass in a given volume |
| sound wave | a longitudinal wave in a medium carries energy |
| elasticity | a property of materials that bend back after a wave passes |
| compression | dense area in a longitudinal wave |
| rarefaction | less dense area in a longitudinal wave |
| frequency | how many waves per second |
| intensity | the force of a sound wave |
| decibel | measure of loudness |
| amplitude | how much energy a wave has |
| sonogram | a picture made by reflecting sound |
| hertz | a measure of frequency |
