How to Determine Nodes and Antinodes in a Closed Pipe?

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SUMMARY

The discussion focuses on understanding standing waves in a closed pipe, specifically one that is open at one end and closed at the other. The key formulas provided are Lambda = 4L/n for wavelength and frequency f = nv/4L, where n represents the harmonic number, which can only be odd integers. The first few harmonics are detailed, indicating that the n-th harmonic has n+1 nodes and anti-nodes combined. For n+1 even, there are (n+1)/2 nodes and (n+1)/2 anti-nodes; for n+1 odd, there are (n+2)/2 nodes and n/2 anti-nodes.

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HumorMe81
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So confused about standing waves in a closed pipe, which is open at one end and closed at the other. The closed end has a node while the open end has an antinode. To figure the wavelength, i use the formula:
Lambda = 4L/n where n is the number of harmonic and can only be odd integers
frequency of the wave, f = nv/4L

How can i figure out the number of nodes or antinodes? For example, the first harmonic is the fundamental frequency and has one node and one antinode. the third harmonic is the first overtone and has two nodes and two nodes. the fifth harmonic is the second overtone and has three nodes and three antinodes. What if I come across a situation where I'm dealing with n=53, is there a formula i can employ to figure out the number of nodes and antinodes?

Thanks!
 
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Draw the first few standing waves and generalize. You will find that the n-th harmonic has n+1 nodes and anti-nodes (combined). If n+1 is even there will be (n+1)/2 nodes and (n+1)/2 anti-nodes. If n+1 is odd, there will be (n+2)/2 nodes and n/2 anti-nodes.
 
Mr.Miyagi said:
Draw the first few standing waves and generalize. You will find that the n-th harmonic has n+1 nodes and anti-nodes (combined). If n+1 is even there will be (n+1)/2 nodes and (n+1)/2 anti-nodes. If n+1 is odd, there will be (n+2)/2 nodes and n/2 anti-nodes.

I tried your recommendation in a problem in my mcat book and it works great. For some reason, the book doesn't discuss how to figure out nodes and antinodes. Thank you so much, really appreciate it!
 
I do not have a good working knowledge of physics yet. I tried to piece this together but after researching this, I couldn’t figure out the correct laws of physics to combine to develop a formula to answer this question. Ex. 1 - A moving object impacts a static object at a constant velocity. Ex. 2 - A moving object impacts a static object at the same velocity but is accelerating at the moment of impact. Assuming the mass of the objects is the same and the velocity at the moment of impact...

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