The Physics of Sound
From the standpoint of physics, sound is an acoustic wave that results when
a vibrating source (such as human vocal cords) disturbs an elastic medium
(such as air). When a sound wave reaches a listener's ear drum, the vibrations
are transmitted to the inner ear (or cochlea), where mechanical displacements
are converted to neural pulses that are sent to the brain and result in
the sensation of sound.
[Berg and Stork provides a good introduction
to the physics of sound. For a more mathematical treatment, see Morse
and Ingard.]
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