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Homework Help: The speed of the electrons in the conductor

  1. Aug 23, 2009 #1
    1. The problem statement, all variables and given/known data
    A copper conductor with a cross-section of A and a lenght of is connected to a battery with a electromotive force of U. The resistance of the conductor is R, and the internal resistance of the battery is negligible.
    U = 220 V
    l = 10 m
    A = 10 mm2
    R = 0.01695 [tex]\Omega[/tex]
    Determine the average speed of the electrons!

    3. The attempt at a solution
    I know the electric current. But I have no idea how many electrons are moving.

    I'm not a native speaker. I may have grammer mistakes.
  2. jcsd
  3. Aug 23, 2009 #2
    I will give u all the equations u need(i think) and try to solve it by urself

    dQ=nqvAdt thus I=nqvA n is the charge concentration, v the electrons velocity, A surface area

    J=I/A J is the current's density


    hope i helped
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