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Where does an electron's kinetic energy go?

  1. Apr 25, 2013 #1
    When an electron moves through a wire between two terminals on a battery some of its potential energy is converted to kinetic energy. My question is, where does that kinetic energy go once it reaches the other terminal? Some of it is probably converted to heat, but what about the rest of it?
  2. jcsd
  3. Apr 25, 2013 #2


    Staff: Mentor

    hw about in the chemical bond that it makes when its attached to an atom?
  4. Apr 26, 2013 #3
    Electrons are very light and move at a rather slow velocity. Their kinetic energy is completely negligible unless your application is a particle accelerator.
  5. Apr 27, 2013 #4


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    Staff Emeritus
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    Gold Member

    Absolutely incorrect. In a room temperature conductor electrons have random velocities which are a significant fraction of c. What is low is the DRIFT velocity imposed but the EMF of a circuit.

    Some Kinetic energy is converted to heat due to interactions with other electrons and the crystal structure.
  6. Apr 27, 2013 #5
    Yes. I was refering to drift velocity. Thank you for the correction.

    I am dubious however about the contribution of kinetic energy to the energy delivered by the circuit, including the energy converted to heat. The energy delivered by the circuit is the energy of electrons moving from higher potential to lower potential.

    Talking about the kinetic energy of electrons in a circuit seems to me like talking about the kinetic energy of the weights that power a grandfather clock. Yes, they do move but it's a stretch to say the clock is powered by their kinetic energy.
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