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Homework Help: Griffiths problem 4.10

  1. Mar 10, 2008 #1
    1. The problem statement, all variables and given/known data
    I have a problem exactly like problem 4.10 in griffiths, however that problem is not being much help since it seems to me that they just plug in P(r).

    For those who do not have griffiths the question is:
    A sphere of radius R carries a polarization P(r)=kr
    where k is a constant and r is the vector from the center
    2. Relevant equations


    3. The attempt at a solution
    answer is sigma=kR

  2. jcsd
  3. Mar 11, 2008 #2
    What do you mean? You need to use the definitions of bound surface and volume charges, which are dependent on P. If by plug in you mean they plug it into the equations, then yes, you just use the definitions.
  4. Mar 11, 2008 #3
    You are right, but that question asks for more
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