Physics help for open and closed pipes

[Hopefullpremed]

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What are the equations for these and what do harmonics mean that they correspond to a wavlength at which sound can be heard? To hear a sound means at least one wavelength as in a pipe closed at one end.

 

[engineeredout]

Okay you're going to have to be a little more clear. You say you want equations for open and closed pipes, do you mean equations like the continuity/bernoulli equation?

And a harmonic is a multiple of a certain frequency. Ex: if you have a frequency f, a harmonic could be 2f.


I feel like I'm not answering your question but I'm not sure what you want exactly.

 

[161927]

For an open pipe, you can subtract the fundamental frequency from any overtone/harmonic to get the n-1 harmonic

ex: f1 = 20 Hz and f3 = 60 Hz; therefore f2 = 40 Hz

For a closed pipe, you cannot subtract the fundamental frequency from any overtone/harmonic to get the n-1 harmonic

f1 = 20 Hz, f2 !== 40 Hz
only the odd frequencies are featured

 

[Hopefullpremed]

For an open pipe, you can subtract the fundamental frequency from any overtone/harmonic to get the n-1 harmonic

ex: f1 = 20 Hz and f3 = 60 Hz; therefore f2 = 40 Hz

For a closed pipe, you cannot subtract the fundamental frequency from any overtone/harmonic to get the n-1 harmonic

f1 = 20 Hz, f2 !== 40 Hz
only the odd frequencies are featured

Odd frequencies means n=1,3,5 but what do numbers 2,4,6 mean since they can exist for open pipes but not closed? Only for fluids or longitudinal waves? For longitudinal waves, does it represent atomic orbital states when they say it has nodes and antinodes? I mean the wave hits the sides of the pipes but what causes to be a perfect wave having odd harmonics?

 

[161927]

Odd frequencies means n=1,3,5 but what do numbers 2,4,6 mean since they can exist for open pipes but not closed? Only for fluids or longitudinal waves? For longitudinal waves, does it represent atomic orbital states when they say it has nodes and antinodes? I mean the wave hits the sides of the pipes but what causes to be a perfect wave having odd harmonics?

When a wavefront strikes a closed-tube boundary, it undergoes a 180° phase shift, much like light striking a surface of higher index of refraction. This changes the path length corresponding to the wavelength and alters the phase relationship between the incoming and outgoing waves. These are longitudinal waves because they are sound waves. A node is a point of deconstructive interference.