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Homework Help: Units Question

  1. Aug 26, 2010 #1
    1. The problem statement, all variables and given/known data
    The velocity of a traverse wave traveling along a string depends on the tension of the string, F, which has units of force, and its mass per length unit u.
    Assume v = F^x * u^y. The values may be found using dimensional analysis.

    2. Relevant equations
    I am pretty sure I understand dimensional analysis. I just don't know what the units are for "mass per length" . I am assuming that the Force is in newtons (kg * m /s^2) and I know velocity is (m/s). Sorry for the goofy question but I'm still waiting on my book to come in from Amazon and I can't to find an answer on Google for mass per length. Thanks

    3. The attempt at a solution
    I don't want help with solving the problem itself. I am just wondering what mass per unit length means so I can solve the question.
    Last edited: Aug 26, 2010
  2. jcsd
  3. Aug 26, 2010 #2
    Nevermind I just figured out it is kg/m
  4. Aug 27, 2010 #3


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    Gold Member

    They are distinguishing between "units" and "dimensions" -- for example, velocity has dimensions length/time no matter what system of units you use. But yes, it's easier just to put the units in.
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