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How they got formula 1.7 from formula 1.6

  1. Mar 20, 2010 #1
    there is no rho in 1.6
    and E dissapeared

  2. jcsd
  3. Mar 20, 2010 #2


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    Staff: Mentor

    I have not the slightest idea what it is all about, but perhaps σρ=1.
  4. Mar 20, 2010 #3
    its about solid state physics and semiconductors
    and there is no rho in 1.6
  5. Mar 20, 2010 #4
    What work have you done so far to find how σ and ρ are related?

    You obviously have gaps in the subject and should review EM before continuing on. It's such a simple relationship.
  6. Mar 20, 2010 #5
    [tex]\sigma =\frac{ne^2\tau }{m}[/tex]

    [tex]E =\rho J[/tex]

    [tex]\tau=\frac{m}{\rho n e^2}[/tex]
    Last edited: Mar 20, 2010
  7. Mar 20, 2010 #6
    here is a hint.

    What is definition of σ?

    What is definition of ρ?

    can you find this out please.
  8. Mar 20, 2010 #7
    thanks :)
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