Longitudal waves - sound waves

AI Thread Summary
A longitudinal wave is defined mathematically as a wave where the displacement is parallel to the direction of wave propagation. When discussing a point source of waves, the wavenumber can appear to change from point to point due to the varying direction of propagation. However, the magnitude of the wavevector remains constant as long as the wavelength of the source does not change. It's important to distinguish between wavenumber, typically used in one-dimensional contexts, and wavevector, which accounts for direction in three dimensions. Understanding these concepts is crucial for analyzing wave behavior in different scenarios.
bubuta
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Hi.
I am looking for correct mathematical definition of longitudal wave I am 3-D
if somebody will help me with some link or explanation it will be great.
Another thing: when I have a point source of waves i see that wavenumber changes from one point to point, is it wright?
thanx
 
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Longitudinal means that the wave number is parallel to the displacement.

Also, please elaborate on what you mean when you say you see the wavenumber changes from point to point with a point source.
 
The wavenumber is a term generally only used in 1 dimension. In general, we use a wave[/I]vector to specify, not just the wavelength of the wave, but also the direction of propagation.

Since, for a point source, the direction of propagation varies with position, the wavevector must too, vary with position. The magnitude of the wavevector however does not vary so long as the wavelength of the source remains constant.

Claude.
 

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