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Flashcards: Sound
Sound
A wave of vibrating particles transferring energy to our ears
Intensity
The loudness of a sound
Amplitude
The size of a sound vibration (the bigger the amplitude the louder the sound)
Frequency
The number of vibrations per second (measured in Hertz)
Pitch
How high or low a note sounds (high pitch is caused by high frequency)
Speed of sound
343 m/s in air
Microphone
A machine that converts sound waves into changes in electrical current or voltage
Oscilloscope
An instrument that shows a picture of sound waves on a screen
Cochlea
Part of the ear that changes vibrations into electrical impulses
Auditory nerve
The nerve that carries impulses from the ear to the brain
Decibel
Unit for measuring the loudness of a sound
Ultrasound
Sound waves with frequencies above 20,000 Hertz (the upper limit of human hearing)
Echo
The reflection of sound
Echolocation
Finding prey or obstacles by emitting sounds and listening for the echoes
Longitudinal wave
A wave in which the vibrations (eg of particles) are in the same direction as the direction of the wave
Transverse wave
A wave in which the vibrations (eg of particles) are at right angles to the direction of the wave