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Homework Help: Drift current calculation drift verlocity not given

  1. Sep 8, 2011 #1
    Calculate drift current.
    length of wire 1m for 10V
    cross sectional area = 0.001m^2
    e = 1.602 x 10^-19
    ue = 3.18 x 10^-7
    n = 10^23 electrons / m^3


    what does ue stand for?
    how do i calculate drift verlocity?

    3. The attempt at a solution

    i am using the formular

    I = nAVq
    where I = current
    n = number of charged particles per unit volume (10^23)??
    A = cross sectional area (0.001)
    V = drift verlocity

    drift verlocity = ue (3.18 x 10^-7) x charge dencity (charge dencity = 10^23 x 1.602 x 10^-19)

    Q = charge on each particle (1.602 x 10^-19)

    therefore

    I = (10^23) x (0.001) x (3.18 x 10^-7 x 10^23 x 1.602 x 10^-19) x (1.602 x 10^-19)

    I = 0.08161 A

    or 81.61 mA

    No idea if any of this is correct please help

    Many thanks

    Rob.
    1. The problem statement, all variables and given/known data



    2. Relevant equations



    3. The attempt at a solution
     
  2. jcsd
  3. Sep 8, 2011 #2

    ehild

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  4. Sep 8, 2011 #3
    I believe that u*e is the drift velocity in m/s where u is "mu" the electron mobility and "e" is the electric field.

    Solve for I

    http://en.wikipedia.org/wiki/Drift_velocity
     
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