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Homework Help: Drift velocity and voltage

  1. Mar 5, 2007 #1
    Not sure if this should be in this forum, but lets try.

    The problem is about 2 samples. One pure Na and one InSb.
    I want to determine the hall voltage when we send a current of 100mA trough the samples and the magnetic field is B = 0.1T. The samples are dimensioned "squared" 5x1x5mm. We send our current into the 5x1 side and out at the opposit side.

    I start with stating F = 0 = q(E +v x B)
    Here I have everything except for the E that I want to find, and v, the driftvelocity of the electrons. How am I supposed to find my v with the information given? Would appriciate if you could show the calulations eventough it's not populair here, having my test soon.

    this is part b of an assignment. In the a part they give m_e* = 0.015m_0 and m_h* = 0.18m_0. Where * means the efficient mass. Dont really think thats needed in the b part, but just to be sure.
  2. jcsd
  3. Mar 5, 2007 #2
    Never mind
    J = N_e *(-e) * v_d
    J = I/A
    I/A = N_e *(-e) * v_d
    v_d = I/(A*N_e*(-e))
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