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Homework Help: Quick question about Rydberg Constant Equations

  1. Feb 11, 2005 #1
    So I have the equation

    1/lambdamn = R(1/(n^2) - 1/(m^2))

    Where m > n, and lambda is the energy emitted by a photon from m going down to n. And I have to get show that this formula can be explained by

    1.) Requiring that light occurs in quanta

    2.) And to get a formula for Energy in terms of R.

    I had previously derived this forumula

    E = - e^2 / 4*pi*eo*an + n^2*(hbar)/^2/2m*an

    where a is the radius of the electron orbit, n will be 1 for our purposes, etc. How do I go about getting an equation for part 2...and how do I even begin part 1?

    Any help is appreciated, thanks!
  2. jcsd
  3. Feb 11, 2005 #2
    It maybe helps to notice that lambda is not the energy but the wavelength of the emitted photon.
  4. Feb 11, 2005 #3


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    How did u get that formula,exactly...?I mean,expressed as a sum of 2 terms,what does each stand for...?

  5. Feb 11, 2005 #4


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    Conservation of energy requires:

    where [itex]E_n>E_m[/itex].

    Use the expression for the nth energy to find R.
  6. Feb 11, 2005 #5
    But what equations do I have for En and Em?
  7. Feb 11, 2005 #6
    Do you know Bohrs model of the hydrogen atom?
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