Sound Energy Vocabulary Words
Sound energy: energy that comes from vibrating particles
Wave: disturbance that carries energy through matter or through empty space
Vibration: small, rapid (quick) back and forth movement
Medium (plural: media): any matter that waves travel through
Mechanical wave: waves that HAVE to have a medium – they can’t travel through empty space
Longitudinal wave: waves in which the particles of the medium vibrate back and forth along the same direction as the wave flows
Compression: the areas where the particles of a longitudinal wave “bunch up” (are compressed)
Rarefaction: the areas where the particles of a longitudinal wave are sparse (are rare)
Wavelength: the space from the middle of one compression to the middle of the compression next door to it
Wave speed: how fast the wave travels
Frequency: the number of waves in a certain period of time, for instance, 20 waves per second
Hertz: the units we use to measure frequency – 20 waves per second would be 20 Hertz (Hz) because one hertz is equal to one wave per second
Pitch: how high or low the sound is; in music, a baritone has a lower pitch than a soprano; in the Spongebob cartoon, Spongebob has a high pitched voice, while Patrick has a low pitched voice
Amplitude: in sound, this determines how LOUD the sound is
Decibel: the units we use to measure how loud the sound is; it is abbreviated dB; a whisper is about 20 decibels, normal talking is about 60 decibels and a chainsaw is about 100 decibels
Reflection: the bouncing back of a sound wave after it hits a surface; echoes in the gym are caused by the sound waves bouncing off the walls, ceiling and floor
Sonar: a machine that uses reflected sound (echoes) to locate things; ships use it to find icebergs
Ultrasonography: you might know this as “ultrasounds”. These are machines that use reflected sound waves to “see” inside a person’s body; pregnant ladies often have ultrasounds to see the fetus inside growing
Resonance: when the vibrations of one object causes another object to also vibrate. You’ve seen film of people shattering a glass with their voices? This is resonance.
Constructive Interference: when the compression of one wave overlap the compression of another wave or waves. This increases amplitude.
Destructive Interference: when the compression of one wave overlap the rarefaction of another wave. The resulting wave has a smaller amplitude that the original waves had.
Honors only:
Tempanic membrane: the “eardrum”, a small piece of skin that is stretched over the ear canal, when you hear me in class, air particles are hitting the tempanic membrane
Hammer, anvil and stirrup: three very small bones in the middle ear that carry the vibrations to the inner ear
Cochlea: a small snail-shaped organ that turns the mechanical energy (the vibration) into electrical energy, which the brain then interprets as “sound”