| A | B |
|---|
| rarefaction | air particles spread out in a longitudinal wave |
| compression | air particles pushed together in a longitudinal wave |
| diffraction | sound waves bending around the edge of an object |
| density | the amount of mass per given volume |
| pitch | how high or low a sound seems to a person |
| loudness | the energy percieved of a sound |
| intensity | the amound of energy a sound wave carries per unit area |
| decibel | a measure of loudness of a sound |
| Doppler effect | a change in frequency of a wave in relation to an observer |
| music | a set of sounds that are pleasing to the ear |
| fundamental tone | the lowest natural frequency of a musical instrument |
| overtone | higher frequencies of an instrument above the fundamental tone |
| ear canal | part of the outer ear which funnels sound to the eardrum |
| eardrum | a small, drum-like membrane in the outer ear |
| cochlea | a liquid-filled cavity in the inner ear that processes sound using tiny hair cells |
| echolocation | the use of reflected sound waves to locate objects or prey |
| ultrasound | sound waves with frequencies above 20,000 Hz |
| sonagram | a device that uses sound to create a picture |
| sonar | a system that uses reflected sound waves to locate objects under water |
| infrasound | sound waves with frequencies below 10 Hz |
