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Homework Help: Polarization charge density

  1. Sep 17, 2013 #1
    1. The problem statement, all variables and given/known data
    We use an accelerator to uniformly implant electrons in a block of lucite, its surface is 25 cm², thickness 12mm.
    The current of the electron beam is 0,1 µA and the implantation takes 1s.
    The electrons are "trapped" in a layer of uniform density of 2mm thickness whose center is at 6 mm of the block surface. The two large surfaces have same potential V=0.

    - Find the polarization charge density ρp in each of the three regions of the block.
    - Find the polarization charge density of surface σp over the two large surfaces of the block.
    2. Relevant equations
    ρ= . D
    Po XeE
    σp= P.n^
    3. The attempt at a solution

    I'd say that outside the layer where the electrons are ρp =0
    And I am really really stuck .. :frown:
    I have to return this before the end of tomorow, and i'm not getting any of this.. I've read the course notes a hundred times
    Thanks !
    Last edited: Sep 17, 2013
  2. jcsd
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