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the maximum distance a wave vibrates from its rest position


a region of higher density or pressure in a wave

Constructive interference

interference that results in a wave that has a greater amplitude than that of the individual waves


(dB) the most common unit used to express loudness

Destructive interference

interference that results in a wave that has a smaller amplitude than that of the individual waves


the bending of waves around a barrier or through an opening

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)


a reflected sound wave


the process of using reflected sound waves to find objects


the number of waves produced in a given amount of time


the lowest resonant frequency


(Hz) the unit used to express frequency; one hertz is one cycle per second


the term describing sounds with frequencies lower than 20 Hz

Inner ear

the part of the ear where vibrations created by sound are changed into electrical signals for the brain to interpret


a wave interaction that occurs when two or more waves overlap


how loud or soft a sound is perceived to be


a substance through which a wave can travel

Middle ear

the part of the ear where the amplitude of sound vibrations is increased


any undesired sound, especially nonmusical sound, that includes a random mix of pitches


a device used to graph representations of sound waves

Outer ear

"the part of the ear that acts as a funnel to direct sound waves into the middle ear"


resonant frequencies that are higher than the fundamental


how high or low a sound is perceived to be


a region of lower density or pressure in a wave


the bouncing back of a wave after it strikes a barrier or an object


what occurs when an object vibrating at or near a resonant frequency of a second object causes the second object to vibrate

Resonant frequencies

the frequencies at which standing waves are made


(sound navigation and ranging) a type of electronic echolocation

Sonic boom

"the explosive sound heard when a shock wave from an object traveling faster than the speed of sound reaches a person's ears"

Sound quality

the result of several pitches blending together through interference

Standing wave

"a wave that forms a stationary pattern in which portions of the wave do not move and other portions move with a large amplitude"


hearing loss resulting from damage to the hair cells and nerve endings in the cochlea


the term describing sounds with frequencies higher than 20,000 Hz


"a medical procedure that uses echoes from ultrasonic waves to "see" inside a patient's body without performing surgery"


the complete back-and-forth motion of an object


a disturbance that transmits energy through matter or space

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