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Homework Help: How do you determine the wavelength of the string?

  1. May 20, 2005 #1
    There is a string 1m in length, 100g in mass and has tension of 10N. 9.5 Hz of frequency is applied to it.

    I know this question is meant to be simple but how do you determine the wavelength of the string?

    Thank you.
  2. jcsd
  3. May 20, 2005 #2


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    Science Advisor

    The wave velocity is given by the square root of (tension over linear density).
    Once you know the wave velocity you can get the wave length from that and the frequency.
  4. May 20, 2005 #3
    The wavelength is one over the frequency, so just divide 1 by 9.5 and that tells you the lenghth of one period or the wavelength.
  5. May 20, 2005 #4
    The linear density has units of kg/m, right? So v = 10/0.1^(1/2) = 10m/s. But when this is substituted into v=wavelength*f, the wavelength is 1.05, which doesn't make sense.
  6. May 20, 2005 #5
    Ok velocity of wave in a string with tension is given by:


    v= \sqrt \frac{T}{m}


    where m=mass per unit length.

    Now apply v=f(Wavelength) to get the answer
  7. May 20, 2005 #6
    I misread the tension (it was meant to be 1N).

    Thanks guys.
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