SOUND UNIT VOCABULARY

SOUND WAVES

Vibrations that spreads away from a

vibrating object• Drop a pebble into a pond the

waves go away from where the pebble was dropped

RAREFACTION

Part of a sound wave where molecules are spread

out

HERTZ

how frequency is measured (one vibration/second

is one hertz Hz)• Unit of measure

VOLUME

how loud or soft something is (depends on the

amount of energy in the sound wave)

DECIBEL

how volume is measured (dB) F 59 Chart of

decibels

ECHO

reflected sound wave (singing in the shower)

ECHOLOCATION

finding things or navigating using sonar (bats,

whales, dolphins use this) Echolocation

DOPPLER EFFECT

change in frequency and pitch as a sound moves

towards or away from you (named for scientist

Christian Doppler who discovered it)

Doppler

QUALITY

what makes a sound different from another sound

of same volume and pitch (2 singers same note,

same pitch, one is better)

FUNDAMENTAL

main or basic (fundamental frequency is the lowest

frequency something vibrates, guitar string after it is

strummed)

OVERTONE

vibrating at a higher frequency (more times) than

the fundamental

RESONANCE

a fullness and richness of sound, build up of

vibration (it “resonates” with you)

MICROPHONE-

an instrument that amplifies sound

ABSORPTION

disappearance of a sound wave into a surface

(think of a towel absorbing) hard surfaces sounds

bounce off, soft ones it absorbs