How to find wavelength with only distance

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Homework Statement


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A metal rod attached to a tube with both closed ends is stimulated to create waves inside the tube.

If:
L = 1.0 m
d = 0.05 m
Speed of sound in air = 340 m/s
Speed of sound in metal = 1,000 m/s

Calculate the value of x using the wavelength of air.

Homework Equations


Frequency = Velocity / Wavelength

The Attempt at a Solution


The frequency of the the metal is the same as the frequency in air, so:

1,000 / (2*1.0) = 340 / wavelength of air

Because the wavelength of the metal is 2 * L.

340 / 500 = wavelength of air
0.68 = wavelength of air

How do I calculate wavelength with only the distance between two nodes (d)? I need x from wavelength according to the problem's instructions so I have to work backwards but I don't know any formulas for this one.
 
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PhizKid said:
How do I calculate wavelength with only the distance between two nodes (d)?

Wavelength is the distance between two nearest nodes = d. Can you clarify what you are trying to find?
 
voko said:
Wavelength is the distance between two nearest nodes = d. Can you clarify what you are trying to find?

I thought the wavelength was the distance between 3 nodes, since between two nodes is only half the cycle. This is where I'm confused...is the wavelength between two nodes, or is the wavelength between 3 successive nodes? Because I thought the distance between two nodes only completed half the cycle.
 
Sorry, you are right. What I meant to say was distance between two crests, which is what the diagram shows, I think.