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# Standing Waves: L = nλ/2, what is n? watch

1. For a string: Length = nλ/2, I think where n is the number of antinodes. Looking at this picture, that seems right. Eg, for this: L=3λ/2 and it has 3 antinodes.

However, for a tube closed at one end, Length = nλ/4, I'm looking at this picture and for the first harmonic, there are two antinodes and for the 2nd harmonic, there are 3 antinodes so it isn't like how it is a string, where n is the number of antinodes.
Attachment 695080695082

So what is n then?
Attached Images

2. n is the number of anti nodes which are the "loops" formed on the standing wave (the points labeled A on the diagram)
3. So for the first harmonic, one anti node is formed on the string. Therefore, the length of the string would be lambda/2 as here n=1

This is half the wavelength of the wave
4. Ladkus has right! n is the multiple of anti nodes in an ermerging standing wave.

n is the number of anti nodes which are the "loops" formed on the standing wave (the points labeled A on the diagram)

So for the first harmonic, one anti node is formed on the string. Therefore, the length of the string would be lambda/2 as here n=1

This is half the wavelength of the wave
You have given two good explanations what deserves a reputation!
So for the first harmonic, one anti node is formed on the string. Therefore, the length of the string would be lambda/2 as here n=1

This is half the wavelength of the wave
But on the first diagram, there are two As for antinodes? The diagrams show more antinodes than loops, rather than the same number like you were saying.

For example, the first harmonic for the open pipe diagram shows two antinodes rather than one like you said, and the label even says that there is an antinode at each end, so two antinodes. Could you explain that to me please?
6. (Original post by Kallisto)
Ladkus has right! n is the multiple of anti nodes in an ermerging standing wave.

You have given two good explanations what deserves a reputation!
I'm a little confused, please could you look at my reply to his post?
7. Hmm I don't think the open tube explains it very well. The first picture does

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