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Homework Help: The velocity of guitar strings

  1. Dec 3, 2011 #1
    Hello again!

    1. The problem statement, all variables and given/known data

    You are designing a two-string instrument with metal strings 35.0 cm long. Both strings are under the same tension. String S[itex]_{}1[/itex] has a mass of 8.00 g and produces the note middle C (frequency 262 Hz) in its fundamental mode. (a) What should be the tension in the string?

    2. Relevant equations
    f=nv/2L
    v=λf
    λ=2L/n
    v=[itex]\sqrt{}T/μ[/itex]

    3. The attempt at a solution

    I believe the first thing I need to do is calculate the velocity of the string. Since we are talking about its fundamental frequency, I set n=1. Therefore given that f=nv/2L, I did (262)(2)(.35)=183.4. Now, I had worked this problem earlier on a black board and my velocity I believe came out to be around 366 m/s, which seems to make much more sense to me, considering the speed of sound in the air is 344 m/s. My question is, for a string or an object to create an audible noise, must the velocity of the string be greater than 344 m/s. And if so, I don't understand what I'm doing differently this time around to produce exactly half the velocity I found last time.

    Hope this was clear enough.

    Thank you!
     
    Last edited: Dec 3, 2011
  2. jcsd
  3. Dec 4, 2011 #2
    Just bumping this at this point...
     
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