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Homework Help: Oscillation frequency of electrons in atoms (Bohr model)

  1. Oct 4, 2014 #1
    1. The problem statement, all variables and given/known data

    Here is a picture: http://puu.sh/bZtAu/82bdc201bc.png [Broken]

    2. Relevant equations

    For force,

    F = (Ze^2)/4 * pi * e0 * R^3) * r

    f = sqrt(k/m) * 1/2pi

    Where e0 = vacuum permeability, 8.854 x 10^-12m
    and r = radius of hydrogen atom, 5.3 x 10^-11m

    3. The attempt at a solution

    I tried just plugging in values,

    For the first one, Ze = 1, right? Edit: I had an epiphany. Is e the constant (1.6 x 10^-19)? If so that makes a lot more sense. I tried it, still got the wrong answer though.


    1/(4pi(8.854x10^-12)(.053x10^-9)^3) * (5.3 x 10^-11) = A very large number F.

    Then, I use that value of F to plug into the second equation,

    f = sqrt(F/m) * 1/(2pi) and I get an extremely large number. Note that for m I use 9.31 x 10^-31 kg -- is that right, or should I be using .511MeV/c^2?

    Should I be using units in terms of meters or nanometers?

    What kind of numbers should I be looking for? Will the frequency be extremely large? I don't have many tries left so I'd like to be sure my answer is right before submitting again. Thanks!
    Last edited by a moderator: May 7, 2017
  2. jcsd
  3. Oct 4, 2014 #2
    I understand a bit more now -- I know what z and Z stand for, and to plug 1.44 for e^2/4pi.
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