(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

In attached figure, a closed tube is placed near a string that is fixed at one end and has a weight attached to its other end. When bridges A and B are positioned at the points shown,plucking the string between A and B causes the tube to resonate at its fundamental frequency. Points a-e divide the length between A and B into 6 equal segments

Next, A is fixed in place, and B is gradually moved toward A while the closed tube is shifted so that it stays at the center of A and B. During this process, the string is repeatedly plucked between A and B. When B is at a certain point, the tube resonates at the next overtone above the fundamental frequency. Which of a-e represents that point? Here, the string's oscillation is only fundamental oscillation

2. Relevant equations

Close tube; L= (2n-1)[itex]\frac{λ}{4}[/itex] ; n= 1,2,3....

String fixed end; λ=2L/n

3. The attempt at a solution

In 2nd period the tube oscillate at f_{3}

L = [itex]\frac{3}{4}[/itex]λ

∴λ_{tube}=[itex]\frac{4}{3}[/itex]L ....(1)

String ; λ_{string}=2L (oscillate at f_{1}) ...(2)

Divide (1)/(2) I got [itex]\frac{λ_{tube}}{λ_{string}}[/itex] = 2/3

From that I guess the point is a point number 2 from first 3 points, so I don't know that I should choose point b or d as my answer. Also, I don't know that my method is correct or not....

Help is appreciated :)

Thanks

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# Homework Help: Close tube with string oscillation

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