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Whats potential energy of a electron left in free space outside atom.?

  1. May 19, 2012 #1
    how does this change with introduction of another charge in its vicinity suddenly..and how does this vary as both charges repel each other after introduction of like charge..
    btw I even wonder whether a electron which is outside a atom is in form of wave or particle..hope my questions are valid..thanks in advance...
  2. jcsd
  3. May 20, 2012 #2
    is my question valid..?
  4. May 21, 2012 #3
    anyone please answer it
  5. May 22, 2012 #4
    good question, just poorly written
  6. May 22, 2012 #5
    aha..if u comprehend what I meant..can't u answer it :p
    Well maybe my idea is represented vaguely But it makes sense..
  7. May 22, 2012 #6
    For a single electron, the potential energy is zero. If you want to bring another electron close to it, you have to overcome their repulsion. The work done by bringing the electrons together is the potential energy of the system. If the other charge is positive, the work done is negative (you don't need to apply force to bring them together) and the potential energy is also negative. This means that you need energy to tear them apart.

    You cannot introduce another charge suddenly (i.e. instantly) that would violate local conservation of charge thus the question is meaningless.

    Electron outside of an atom is neither wave nor particle, much like anything else in QM. However it is best described by it's particle-like properties: it's localized and has momentum and position.
  8. May 23, 2012 #7
    well this is interesting, suppose both charges are neutral..now there is a potential developed between them due to masses,how is this potential different to EM potential(well I know magnitude of these differ but what about other factors,like time dilutes in this case as same as that case(due to gravity))..and for this process how conservation of momentum can be attributed,does charge 1 move away while introducing like charge..thanks in advance..ur previous explaination was praiseworthy
  9. May 23, 2012 #8


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    A potential energy is always arbitrary - it is convenient to use 0 for a free electron, but you can assign any value you like to it. Only potential differences are meaningful quantities.

    I don't understand the scenario of your last post. With (Newtonian) gravity, it is like electromagnetism. With General Relativity, calculations are much more difficult, and you lose the possibility to describe everything in a flat spacetime.
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