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Homework Help: A dimensional analysis problem.

  1. Jul 13, 2008 #1
    1. The problem statement, all variables and given/known data
    Basically, I have a constant that is 1/mass. I need to find out how to relate this to my function which has units eV/A^2 to have results in THz^2.


    2. Relevant equations



    3. The attempt at a solution
    I think I would just have the mass in units of MeV/c^2 and then convert c^2 into A^2/s^2... Does this sound correct?
     
  2. jcsd
  3. Jul 13, 2008 #2

    Redbelly98

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    I think that will work, since A seems to be a length unit (Angstroms?) from what you say.

    Let's see ... reciprocal of mass in your units would be c^2/eV, so:

    [tex]
    \frac{c^2}{eV} \cdot \frac{eV}{A^2}
    = \frac{A^2}{s^2 \cdot eV} \cdot \frac{eV}{A^2}
    = \frac{1}{s^2}
    = Hz^2
    [/tex]
     
  4. Jul 13, 2008 #3
    Yeah, it was Angstroms. That's what I was thinking it would be, was just wanting to run it through with someone else before I started over again. Thanks. :)
     
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