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Homework Help: Wavenumber, transitions

  1. Sep 6, 2010 #1
    1. The problem statement, all variables and given/known data
    Calculate a diameter of an H-atom with n=732. Calculate also the value of the wavenumber corresponding to the transition from n=732 to n=731




    2. Relevant equations

    [tex] E_{trans}= \frac{-E_{h}}{(732)^2}-\frac{-E_{h}}{(731)^2}}[/tex]



    3. The attempt at a solution

    [tex] E_{trans}= \frac{-13.6}{(732)^2}-\frac{-13.6}{(731)^2}}=6.95\cdot10^{-5} eV[/tex]

    [tex] E=\frac{hc}{\lambda}\Rightarrow \lambda=\frac{hc}{E}=\frac{4.135\cdot10^{-15}\cdot 3\cdot10^8}{6.95\cdot10^{-5}}=0.0178 m[/tex]
    1. The problem statement, all variables and given/known data

    now going back to the wavenumber, i was not sure which formula i should use....
    [tex] k=\frac{2\pi}{\lambda} or \nu=\frac{1}{\lambda}[/tex]
    I have chosen the second one and i got
    [tex] \nu=\frac{1}{0.0178}=56.18 m^{-1}[/tex]
    1. The problem statement, all variables and given/known data

    Is that a relevant result?







    3. The attempt at a solution

    the diameter will be=
    [tex] d_{n}=2\cdot r_{0}\cdot n^2= 2\cdot (732)^2\cdot 5.291\cdot10^{-5} = 5.67\cdot10^{-5} m[/tex]
     
    Last edited: Sep 6, 2010
  2. jcsd
  3. Sep 6, 2010 #2
    Seems OK :)
     
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