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B What defines electric energy?

  1. Nov 29, 2016 #1
    In most textbooks the electric energy is merely mentioned, not explained. From a google search the definition states that electric energy is the movement of electrons. But what exactly is it? It is obvious that it does work by transferring the potential energy to kinetic energy. So is electric energy another term for kinetic energy?
     
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  3. Nov 29, 2016 #2

    BvU

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    No, it is a separate form of energy. It takes work (= energy) to move a charge from infinity to the neighborhood of an identical charge (fixed to its location for simplicity).
     
  4. Nov 29, 2016 #3
    So since it is another form of energy, would electric energy just be the work done to move an electron from zero potential to a potential? So electric energy = work done? If so, can I equate this work done to kinetic energy so work(electric energy) = kinetic energy?
     
  5. Nov 29, 2016 #4

    BvU

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    Yes, yes and yes.
    That is correct. If you let go of a charge A in the neighborhood of an identical charge B (that is fixed to its position), the electric energy will be converted to kinetic energy of A. Note the kinetic energy of A at time ##t## is the difference in electric energy between its original position and its position at time ##t##.

    Or: a charge A let go in the neighborhood of an opposite charge B (fixed) will move toward B and the kinetic energy of A will be the difference in electric energy.
     
  6. Nov 29, 2016 #5

    sophiecentaur

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    It would be better to re-state that and to say that electricity is 'associated with' the movement of electrons (mostly, in our practical experience of Electricity).
    It is not a good idea to demand such a 'concrete' description of Electricity and to want to include electrons in explanations. Electricity is a very abstract entity which can be described best by using a mathematical description. Look at any text book for confirmation of that statement. It is not a cop out - using electrons is actually the real cop out, in my opinion.
     
  7. Nov 30, 2016 #6

    ZapperZ

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    There is a little bit of confusion, and of ships passing in the night, here.

    To the OP: are you asking for how we gain energy in electricity, as in when we plug in our appliances into the wall outlet, or when a light bulb lights up? Or are you asking about how energy is gained or lost in an electric field due to movement of charges?

    While those two may appear to be the same (and they essentially are based on the underlying theory), the more basic explanation isn't the same for both. You appear to have been given both answers, but it is difficult to know which one you are looking for without a clearer definition of what "electric energy" is.

    Zz.
     
  8. Nov 30, 2016 #7
    I'm guess I'm essentially asking for both, but aren't the two essentially the same? Since you need an electric field to push the electrons in a circuit.
     
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