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Homework Help: Magnetism Problem

  1. Apr 16, 2005 #1
    Which is the correct equation for Magnetic Reluctance ?

    [tex] R [/tex] = Reluctance
    [tex] l [/tex] = Length
    [tex] A [/tex] = Area
    [tex] \mu [/tex] = Magnetic Permeability of the material
    [tex] \mu_0 [/tex] = Magnetic Permeability of free space ([tex] 4\pi \times 10^- ^7 [/tex] tesla/ampere turn)

    [tex]R = \frac {l} {\mu A}[/tex] as stated on Wikipedia or [tex]R = \frac {l} {\mu_0 \mu A}[/tex] as stated in my text book.
  2. jcsd
  3. Apr 16, 2005 #2

    Doc Al

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    Staff: Mentor

    The Wikipedia formula looks correct. Are you sure your book isn't using [itex]\mu[/itex] to mean relative permeability (which is just a ratio)? (If not, the units would make no sense in your book's formula.)
  4. Apr 16, 2005 #3
    Thanks very much that would be it. "Relative Permeability"
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