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Motion of a photoelectron

  1. Aug 25, 2011 #1
    if an atom absorbs energy just equal to work function what happens to motion of photoelectron?
  2. jcsd
  3. Aug 25, 2011 #2
    Einstein's photoelectric equation says that the KE of the photoelectron will be zero.
  4. Aug 25, 2011 #3
    I don't think the electron is ejected....
  5. Aug 25, 2011 #4
    But there is enough energy for the electron to escape from the surface.
  6. Aug 25, 2011 #5


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    People are responding to this question as if it is clear what is being asked. Maybe I know this area too much that I can't see the forest, but what exactly is meant by "motion of photoelectron"? There are several different motions here, and it is unclear how much in detail this member is asking. There is the motion of the electron while STILL in the material, and then there's "motion" (or lack there of if it has zero KE left) once it left the surface of the material.

  7. Aug 25, 2011 #6
    yes, but maybe we can assist by answering a question.....as we all know asking the RIGHT question is usually not easy....
  8. Aug 26, 2011 #7
    Why do you think that will happen??
  9. Aug 27, 2011 #8
    ... because that is what 'work function' means. If it has that much energy it will have enough to get to the surface.
  10. Aug 27, 2011 #9
    Exactly...JUST enough energy toget to the surface....so would it not TEND to return to it's former state??

    I am not claiming that, but simple logic seems to suggest it....
  11. Aug 27, 2011 #10


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    See, this is exactly what I meant when I said that the question is vague, but you think it can still be "answered". When you start splitting hairs and want to know what exactly is going on AT the work function energy, then the details now make a heck of a difference!

    For example, did anyone bother to look up Spicer's 3-step model of photoemission? Or did anyone even consider all the components that make up this so-called "work function"? Yet, we seem to think that we can easily answer such a question.

    The OP did a post-and-run. He/she hasn't come back yet to offer any response, while leaving the rest of us holding the bag and arguing what's in it. Consider that for a minute.

  12. Aug 31, 2011 #11
  13. Sep 1, 2011 #12
    One step model is way better :)
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