| A | B |
|---|
| sonar | Technique of using sound waves to measure distance. |
| infrasonic | Sound below the range of human hearing. |
| Doppler effect | Change in sound or light that occurs whenever there is motion between the source and its observer. |
| acoustics | Science of sound and its interactions. |
| pitch | Property of sound that depends on frequency. |
| ultrasonic | Sound above the range of human hearing. |
| outer ear | Part of the human ear that funnels sound wave into the ear. |
| eardrum | tretched membrane in the ear that vibrates at the same frequency as the sound waves that enter the ear. |
| middle ear | Part of the ear that receives vibrations from the eardrum and contains the hammer, anvil, and stirrup. |
| inner ear | Liquid-filled portion of the ear. |
| cochlea | Part of the ear that contains hundreds of nerve cells attached to nerve fibers. |
| compression | place in a sound wave where particles are squeezed together |
| rarefaction | the place in sound waves where the particles are spread farthest apart |
| Volume | a measure of how loud or soft a sound is |
| amplitude | the height of a sound wave |
| pitch | how high or low a sound is |
