a pressure on time graph of 20 ms recording of clarinet tone demonstrates 2 fundamental elements of sound: pressure , time.
sounds can represented mixture of component sinusoidal waves of different frequencies. bottom waves have higher frequencies above. horizontal axis represents time.
although there many complexities relating transmission of sounds, @ point of reception (i.e. ears), sound readily dividable 2 simple elements: pressure , time. these fundamental elements form basis of sound waves. can used describe, in absolute terms, every sound hear.
however, in order understand sound more fully, complex wave such separated component parts, combination of various sound wave frequencies (and noise).
sound waves simplified description in terms of sinusoidal plane waves, characterized these generic properties:
frequency, or inverse, wavelength
amplitude, sound pressure or intensity
speed of sound
direction
sound perceptible humans has frequencies 20 hz 20,000 hz. in air @ standard temperature , pressure, corresponding wavelengths of sound waves range 17 m 17 mm. speed , direction combined velocity vector; wave number , direction combined wave vector.
transverse waves, known shear waves, have additional property, polarization, , not characteristic of sound waves.
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