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Some terms and definitions! :-)


the highest point of a wave

communication tools

the various ways sound waves are used (musical instruments, voice, animal sounds, morse code, and telephone)


where a sound wave pushes matter together


how the loudness of a sound is measured

Doppler Effect

change in the apparent frequency of a wave, because either the source of the wave is moving toward or away from the observer, or the observer is moving toward or away from the source of the wave (car blowing its horn as it passes by a person on the street)

echo location

animals such as bats and dolphins use this by bouncing sound off objects to determine distance


the number of vibrations in a given unit of time; how fast an object vibrates (measured in Hertz, Hz)

Morse Code

a series of long and short signals standing for letters of the alphabet that are sent over wires


how high or low a sound is determined by the frequency of a vibrating object (Objects vibrating faster have a higher pitch than objects vibrating slower. Larger objects vibrate more slowly and have lower pitch than smaller objects.)


where a sound spreads matter apart


the amplication of sound by increasing the force of its vibration (when a plucked guitar string causes the entire body of the guitar to move)


a device that reflects sound by sending out high frequency sound waves and recording the time it takes to return to the source


a form of energy produced and transmitted by vibrating matter


the lowest point of a wave


a device used by doctors to see inside the body by using sound waves to bounce off such things as bone, muscle, or organs


the rapid back and forth motion of an object


a disturbance moving through a medium (solid, liquid, or gas)


the distance between two compressions

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