Limit to number of standing waves in pipes?

AI Thread Summary
Each pipe has a limit to the number of harmonics it can produce, determined by the relationship between frequency and wavelength. As harmonics increase, the wavelength decreases, but there is a theoretical minimum wavelength related to molecular vibrations. When wavelengths approach this limit, the classical equations of wave behavior become less applicable. This limit results in higher frequencies that exceed the audible range for humans. Ultimately, while there is a maximum number of harmonics, practical constraints arise at very high frequencies.
eknox123
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Homework Statement


This is a conceptual question I had not related to a specific problem- so I know with each higher harmonic in pipes that the frequency increases a certain amount (the fundamental frequency- and that in pipes closed at one end skips the even harmonics). However I also know that frequency is inversely proportionate to wavelength. So each successive harmonic has a smaller wavelength. But since there's a limit (I assume) to how small a wavelength can be, does each pipe have its own limit in terms of the number of harmonics that can be made in it?


Homework Equations


v= wavelength * frequency


The Attempt at a Solution


As I wrote above, I'm guessing there is a limit- like the highest harmonic is the one with the lowest non-zero wavelength (that will be the highest frequency), but I'm not sure if my class is oversimplifying it, and really there are exceptions or something
 
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welcome to pf!

hi eknox123! welcome to pf! :wink:
eknox123 said:
… frequency is inversely proportionate to wavelength. So each successive harmonic has a smaller wavelength. But since there's a limit (I assume) to how small a wavelength can be, does each pipe have its own limit in terms of the number of harmonics that can be made in it?

i suppose that when you get near the molecular level, the random thermal vibrations predominate, and the equations stop working, and so you can't have wavelengths shorter than that …

but I'm guessing that's a lot higher-pitched than any ear can hear! :smile:
 
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