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Question about the nature of electrons and the strong force

  1. Oct 16, 2009 #1
    How can electrons that make up a current not repel each other at far distances due to their like charges? I understand why protons are bunched up together , because of the strong force. Though electrons are not packed up against one another like protons and neutrons, they are still a short distance apart from each other thats needed to create a current. Since the strong force is not governing the motion of electrons, what phenomena prevents electrons from spreading far apart from each other?
  2. jcsd
  3. Oct 16, 2009 #2
    Electrostatic attraction to protons or to nuclei. The average positive and negative charge densities in metals are equal.
  4. Oct 16, 2009 #3
    How does your explanation answer my question about why electrons do not widely fly apart but instead you can bring electrons close enough to each other to produce a current?
  5. Oct 16, 2009 #4
    If the electrons fly apart, the positively charged nuclei will remain and create such an attractive field that the electrons will return to neutralize it.
  6. Oct 16, 2009 #5


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    There are a couple of issues here. Inside an atom, the electron is bound by the attraction of the positive charge of the nucleus.

    As to a current, this is usually modeled by a lattice arrangement where electrons have a degree of freedom to move from atom to atom.

    So the presence of "extra" electrons and atoms with "missing" electrons (within the lattice structure) leads to a current from one place to the other. The net result being a more stable arrangement, in simple terms. It is not that hard to bring one electron near another, although clearly the repulsive force increases as they get closer. So generally, if the atom is not binding them, they do tend to repel. There are other fundamental issues as well, such as the Pauli exclusion principle.

    So if there is something specific you are driving at, you might want to lay that out.
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