What Does a Graph of Sound Wave Pressures in the Atmosphere Reveal?

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Sound waves in the atmosphere consist of alternating dense and thin air regions, with sound pressure levels (SPL) measured in pascals (Pa). The 0-dB SPL is defined as 2 x 10^-5 Pa, serving as the baseline for measuring sound pressure. Street traffic noise is cited as having a pressure of 0.2 Pa, which is significantly lower than atmospheric pressure of about 105 Pa. The discussion clarifies that the values in the table represent pressure variations around the ambient pressure, not absolute atmospheric pressure. Additionally, there is a request for a graph illustrating the energy required to produce sound at various decibel levels, emphasizing the distinction between power and energy.
physea
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Sound waves transmit in atmosphere as dense and thin areas of air. Is there a graph showing the highest and lowest pressure of atmosphere for sound waves of various decibels?
 
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According to this page:

http://www.acoustic-glossary.co.uk/sound-pressure.htm

the 0-dB sound pressure level (SPL) in air is defined as 2 x 10-5 Pa. This is the root-mean-square difference between the instantaneous pressure and the ambient pressure (the pressure that you would have if there were no sound at all). For other SPLs, you can use the table or the formula given on that page.
 
I see 'street traffic' noise pressure is 2 Atm. What does that mean? That pressure the high pressure regions and what the low have in the atmosphere?
 
physea said:
I see 'street traffic' noise pressure is 2 Atm. What does that mean? That pressure the high pressure regions and what the low have in the atmosphere?
The pressures are given in Pa and not atmospheres.
 
nasu said:
The pressures are given in Pa and not atmospheres.

I already know that and I converted them to Atm.
 
Check your conversion factor. 0.2 Pa (which the table shows for "street noise") is much much less than 1 atm.
 
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physea said:
I see 'street traffic' noise pressure is 2 Atm. What does that mean? That pressure the high pressure regions and what the low have in the atmosphere?
Atmospheric pressure is about 105Pa and traffic noise is about 0.2Pa, which is a tiny fraction of that. I can't think where you got your "2 Atmospheres" from.
 
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The pressures in the table are the amplitudes of the pressure variations around the average value (the pressure in the air without sound waves, po).
A value of 2 Pa in the table means that the pressure in the sound wave can be between p0-2Pa and p0+2Pa . Even for the noise so strong that it can damage the ear, the variation are very small compared with the atmospheric pressure.
 
I am looking for a graph of the energy we need to produce a sound of x dB with current technology. Any hint?
 
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physea said:
I am looking for a graph of the energy we need to produce a sound of x dB with current technology. Any hint?
You would mean Power, not Energy. (Important distinction).
Did you ever try this wiki link?
 

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