Sound waves and amplitudes Problem

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SUMMARY

The discussion centers on the relationship between sound wave properties, specifically amplitude, wavelength, and frequency. It is established that while amplitude measures the size of the wave, it is independent of wavelength and frequency. The misconception that the intensity of a sound wave correlates with the amount of air transported is clarified; in a linear acoustic wave, air does not experience net transport. Instead, the energy of the wave relates to the square of the amplitude, affecting the wave's ability to travel further.

PREREQUISITES
  • Understanding of sound wave properties, including amplitude, wavelength, and frequency.
  • Basic knowledge of linear acoustic waves and their behavior in air.
  • Familiarity with the concepts of energy and intensity in wave mechanics.
  • Ability to interpret sine wave graphs and their characteristics.
NEXT STEPS
  • Research the relationship between wave energy and amplitude in sound waves.
  • Study the principles of linear acoustics and their implications for sound propagation.
  • Explore the mathematical definitions of amplitude, wavelength, and frequency in wave theory.
  • Learn about the effects of pressure and velocity on sound wave behavior in different mediums.
USEFUL FOR

Students studying physics, acoustics professionals, educators teaching sound wave concepts, and anyone interested in understanding the mechanics of sound propagation.

alingy1
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1. If there is a sound wave traveling in the air, will the amount of air transported by the wave be proportional to the intensity of the wave?
Here is my answer: yes, because as the energy of the wave is related to the square of the amplitude of oscillations, the more energy you have, the more the wave will be able to travel further and the more amount of air will be affected. My teacher said this is wrong and gave me 0. Why?

2. Is the amplitude independent of the wavelength and frequency?
Here is my answer: yes, the wave speed in the medium determines wavelength and frequency, but amplitude is separate. I got half points for this one.

What is wrong here?
 
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I can't answer your first one because I haven't done sound stuff in a long time, however, for question two:

Correct: Yes
Incorrect: The wave speed in medium

Amplitude is a measure of how big the wave is. Wave length is the distance between crest-crest or trough-trough and frequency tells us how many waves are passing a point per second. Bringing in medium and wave speed is kind of unrelated to the question so it in a way shows you don't really know what you are talking about.

You can think of it like this.
If you look at a sine graph. The amplitude is 1. (The highest it can be is 1, and lowest is -1)
However if I change the distance between the waves, the amplitude still stays as 1. This is because frequency and wavelength, doesn't change the "size" of the wave, they affect the distance between two points on a wave.

Hopefully I explained that well enough.
 
alingy1 said:
1. If there is a sound wave traveling in the air, will the amount of air transported by the wave be proportional to the intensity of the wave?
Here is my answer: yes, because as the energy of the wave is related to the square of the amplitude of oscillations, the more energy you have, the more the wave will be able to travel further and the more amount of air will be affected. My teacher said this is wrong and gave me 0. Why?

In a linear acoustic wave in air, the air moves back and forth so there's no net transport (of mass) at all.

The air transported during each back-and-forth motion is affected by the pressure and the velocity in a more complicated way, but I don't think this is what the question is asking.
 

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