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A string has a mass per unit length of 9 10–3 kg/m. What must be the tension in the string if its second harmonic has the same frequency as the second resonance mode of a 2m long pipe open at one end? The length of the string is 1.5 m.

this is my solution

http://screensnapr.com/e/u4kvtH.png

i just want to ask if my second resonance mode understanding is correct.

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closed as too localized by Qmechanic Feb 15 '13 at 15:37

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What specifically do you suspect you might be doing incorrectly? –  David Z Feb 15 '12 at 17:56
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I did the calculation without first looking at yours (to make sure I wasn't influenced by any mistakes you might have made!) and got the same result, which is reassuring as I first learned this physics 35 years ago :-).

This is obviously a homework problem. I wonder if the point your professor is trying to make is that the first overtone of the string is double the frequency of the fundamental, but the first overtone of a closed pipe is three times the frequency of the fundamental.

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tnx bro. 35 years wow –  IvanMatala Feb 16 '12 at 11:05
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You'll be that old one day, and if I'm not dead I'll laugh :-) –  John Rennie Feb 16 '12 at 11:20
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