Question:
Why do low pitched sounds travel farther than high
pitched sounds?
Replies:
One reason is the different wavelengths. Low pitched sounds have
wavelengths of around 10 feet or more; high pitched sounds have
wavelengths of around an inch or less. As sound travels through
nonuniform air (pressure differences resulting from temperature
differences and from wind; humidity differences resulting from puddles,
animals breathing, trees, etc.) it's speed and direction vary by small
amounts. Small changes in speed and direction result in a sound wave
interfering with itself, and the extent of the interference depends on
how the speed variations and pathlength differences compare with the
wavelength. A path difference of a quarter of an inch could result in
complete cancellation of short wavelength sound but would have a barely
noticeable effect on long wavelength sound.
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