Formula for sound dissipation in air?

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SUMMARY

The dissipation of sound waves in air is governed by the equation I = P / (4πr²), where I represents intensity, P is the power of the sound source, and r is the distance from the source. This equation illustrates that sound intensity decreases with the square of the distance from the source. Additionally, sound absorption is frequency-dependent and proportional to humidity, leading to an attenuation effect that increases with distance. Both the inverse square law and the absorption effects occur simultaneously in sound propagation.

PREREQUISITES
  • Understanding of sound wave propagation
  • Familiarity with the inverse square law
  • Knowledge of sound absorption principles
  • Basic concepts of frequency and humidity effects on sound
NEXT STEPS
  • Research sound wave propagation in different mediums
  • Explore the effects of humidity on sound absorption
  • Learn about the mathematical modeling of sound intensity
  • Investigate real-world applications of sound dissipation equations
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Acoustics engineers, physicists, audio professionals, and anyone interested in the principles of sound propagation and dissipation in air.

Ralphonsicus
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Is there an equation that deals with the dissipation of sound waves in air? As in, how much they die out with distance, because we know they must, otherwise you could hear me talking now!
 
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The intensity is inversely proportional to the radius squared.

That is, if a certain source has a power P and it emits pressure waves spherically, the intensity I you'll hear is

I = \frac{P}{4\pi r^2}
 
There is also some absorption, which depends on frequency (proportional to frequency squared) and humidity. This produces an attenuation which is proportional to distance (as opposed to inverse square law). Both effects occur at the same time.

See this link.
 

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