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Homework Help: Electron energy levels

  1. Apr 15, 2006 #1


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    The question is:

    So I have the equation to find the energy in an infinite well…

    [tex] \[
    E_n = n^2 \frac{{\pi ^2 (\hbar c)^2 }}{{2mc^2 L^2 }} \\
    L = 2*10^3 nm \\
    m = 5.11*10^5 eV \\
    \hbar c = 197.33eV*nm \\

    Using this, I find n=1 to equal 9.40*10^-8 eV

    The book says im good there.

    The problem is when I have to find the second energy level. I figured you use n=2 which means its just 2^2 or 4 times the energy but the book says its just 2 times the energy of the first energy level. What am I not understanding here?
  2. jcsd
  3. Apr 20, 2010 #2
    I'm pretty sure the book made a mistake. For n=2, E2 = 4*E1 = 3.8 X 10^-7. I double checked with cramster, and that's how it was done there also.
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