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Homework Help: Electron energy levels in Bohr model

  1. Feb 7, 2014 #1
    1. The problem statement, all variables and given/known data
    At the bottom of this linked-to screen below is an equation for E = - .......... = - ............. = - 13.6 Z^2 / n^2 eV


    2. Relevant equations

    I'm using the following values for the formula

    K sub e = 8.987 x 10^9 (Coulombs constant)
    e = 2.71828
    m sub e = 9.11 x 10^-31 (mass of electron)
    h-bar = 1.05 x 10^-34

    3. The attempt at a solution

    But when I plug these values in I get (4.017x10^-9) / (2.205 x 10^-68) = - 1.82 x 10^59

    and not -13.6 eV

    What am I doing wrong? Are any of my values above incorrect?
  2. jcsd
  3. Feb 7, 2014 #2


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    Homework Helper
    Gold Member
    2017 Award

    You have misinterpreted the meaning of e in the equation.
  4. Feb 8, 2014 #3
    Thanks TSny!
  5. Feb 8, 2014 #4
    I'm trying to write a simple Excel program to allow use of that formula.

    I've included my program and the formula in the Excel attachment. Would anyone know why I'm getting the VALUE! message in the A5 box?

    Attached Files:

  6. Feb 8, 2014 #5
    Your data values are interpreted as text, not as formulae. Add = in front of them. Also, make sure you format the result cell as a scientific number, otherwise it will just display 0.
  7. Feb 8, 2014 #6
    Thanks voko!
  8. Feb 8, 2014 #7
    I've attached the updated Excel file again.

    The cell A5 displays the value in eV, currently set for n=1.

    If I want to obtain the different values of Energy but for each of the values of n between 1 and 10 inclusive, how would I do this?

    Attached Files:

  9. Feb 8, 2014 #8
    This question has very little to do with physics and much to do with using Excel. You should be asking in a more appropriate section of the forum.

    Your question is very basic. There are probably a lot of online tutorials addressing that.
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