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How does an electron carry energy in a circuit?

  1. Feb 1, 2013 #1
    By what means does an electron carry energy in a circuit? What physical aspect of the electron is changing under the influence of say 6 V versus 12 V?

    Kinetic energy doesn't explain it as electrons at later points in the circuit would be slower and bog down higher-energy electrons in earlier parts of the circuit.
  2. jcsd
  3. Feb 1, 2013 #2
    Maybe think of the electric fields as carrying the energy. That is what your device is 'using' when its hooked up to voltage, its using the electric field and its properties to do work. In this sense the role electrons play is to rearrange themselves so that you get the electric field you want out of the wire. The 'aspect of the electron' that is changing is its position which in turn changes the electric field.
  4. Feb 1, 2013 #3
    That makes sense, thank you. And if you or someone else could refresh my memory: is the electric field generated by exchange of virtual photons between electrons? Or if not, how is it composed?
  5. Feb 1, 2013 #4


    Staff: Mentor

    By what means does a boulder carry energy down a hill? By its position (i.e. potential energy due to position).

    Electrons are so light that their KE is completely negligible in most circuits.
  6. Feb 1, 2013 #5


    User Avatar

    Staff: Mentor

    They are the force carriers of the EM interaction, yes. The subject of virtual particles is very complicated and I highly advise you to simply ignore them unless you are dealing with the various Quantum theories that use them.
  7. Feb 2, 2013 #6
    This is not so easy question.

    An electron in the wire feels that other electrons are pushing it, equally from all directions.

    If we ask the electrons, if they are carrying energy, they might say: "we are storing electrick energy, and we are moving relative to the atoms in the wire, because the atoms are all moving to the same direction"

    If we look at some electrons that seem to be squeezed together, and the electrons seem to be moving to the right, then it is a correct thing to say that electric energy is moving to the right, relative to us.

    But, if we start walking to the right, faster than the electrons, then we must say that electric energy is moving to the left, relative to us.
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