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Homework Help: Energy uncertainty of an atom in an excited state

  1. Dec 4, 2012 #1
    1. The problem statement, all variables and given/known data

    A Na atom is in an excited state for a mean time of [itex]1.6 \times 10^{-8}s[/itex]. Then it jumps to the ground state emitting a photon with 2.105 eV of energy. Find the energy uncertainty of that excited state.

    2. Relevant equations

    3. The attempt at a solution

    I don't even know where to start. Any help would be appreciated!
  2. jcsd
  3. Dec 4, 2012 #2
  4. Dec 4, 2012 #3
    I just don't know how to use that to solve the problem. Could you be more specific?
  5. Dec 5, 2012 #4
    Could it be [itex]\Delta E > \frac{\hbar}{2} \frac{1}{\Delta t} = 32.96 \times 10^{-28}J [/itex]?
  6. Dec 6, 2012 #5
    Doesn't seem to be correct. What you did basically? And the question mentions Na atom , so we cannot use bohr equations. Also I don't know why they gave you energy of de-excitation. There is no use of it , I guess.... I think you used the correct equation but did not solve it correctly.
    Last edited: Dec 6, 2012
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