Intensity of two sound pressure waves

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SUMMARY

The intensity of sound pressure waves is directly proportional to the square of the amplitude and the square of the frequency, while inversely proportional to the square of the radius. In the discussion, it is clarified that when comparing two sound sources, the areas of the waves are irrelevant if both sources are equidistant from detectors with identical areas. The key takeaway is that the intensity comparison should focus on the readings from the detectors rather than the areas of the waves themselves.

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  • Understanding of sound wave properties, including amplitude and frequency
  • Knowledge of the inverse square law as it applies to sound intensity
  • Familiarity with basic physics concepts related to wave behavior
  • Ability to interpret graphical representations of sound waves
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  • Research the mathematical relationship between amplitude, frequency, and intensity in sound waves
  • Study the inverse square law and its implications for sound propagation
  • Explore methods for measuring sound intensity using detectors
  • Learn about the effects of distance on sound intensity and how to calculate it
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Acoustics engineers, physics students, audio technicians, and anyone interested in understanding sound wave behavior and intensity comparisons.

iQadmat
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Homework Statement
Ans: C

I tried to use the intensity formulae and after manipulating it got an expression which gave me wrong answer.
It seems the areas are not equivalent somehow, any explanation?
Relevant Equations
I = P/A
1658379625863.png

1658379637746.png
 
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Hi @iQadmat and welcome to PF.

How does the intensity depend on the amplitude? You can read the amplitudes of the two waves off the graph and compare.
 
kuruman said:
Hi @iQadmat and welcome to PF.

How does the intensity depend on the amplitude? You can read the amplitudes of the two waves off the graph and compare.
Hi and thanks for welcoming me!

I know the intensity is directly proportional to amplitude^2 frequency^2 and inversely proportional to radius^2, but my point was the areas (which I showed in ss) are different somehow and I want to understand the differences between them and what they represent.

So far my understanding*
[The initial 'A' is showing the area at which the power from source is acting upon but the final 'A' (later derived from 'F') is not the initial 'A' but is the area of the wave particle which times by pressure of wave equals 'F' .]
 
The areas are irrelevant. This is a comparison of intensities of two different sources at the same point in space and time. If you must, assume that the two sources are at the same distance from two detectors with identical areas. Compare the detectors' readings. Clearly, wave 2 has greater intensity than wave 1. By what factor?
 
kuruman said:
The areas are irrelevant. This is a comparison of intensities of two different sources at the same point in space and time. If you must, assume that the two sources are at the same distance from two detectors with identical areas. Compare the detectors' readings. Clearly, wave 2 has greater intensity than wave 1. By what factor?
I got it now, Thanks for your help!
 
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