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Magnetic field intensity and density

  1. Oct 25, 2015 #1
    Hello folks,

    Can anyone explain to me what is the difference between magnetic field intensity H and magnetic field density B?
     
  2. jcsd
  3. Oct 25, 2015 #2

    Henryk

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    Hi
    In the simplest terms, the magnetic field intensity H relates to the sources of the magnetic field. For example, the integrated H in a magnetic loop is related to the total current enclosed by the loop (time-independent) by the relation
    $$ \oint \vec H \cdot d \vec l = I $$
    This equation is true regardless of the magnetic permeability of the loop.
    whereas intensity B describes effects of the magnetic field. Examples are Lorentz force on a charge moving in the magnetic field ##\vec F = q (\vec B \times \vec v) ##
    and induced EMF in, say, a single winding of a transformer ## EMF = - \frac d {dt} \iint \vec B \cdot d \vec S ##
     
  4. Oct 26, 2015 #3
    That means B is property of material since it depends on the magnetic permeability of the loop.
     
  5. Oct 27, 2015 #4

    Henryk

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    Well, strictly speaking, the property of the material is the magnetization vector, usually denoted as M. B is the total effect of the source field H and material response in terms of polarization M, such as ## B = \mu _0(H +M)##
     
  6. Oct 29, 2015 #5
    Thanks!! Can you provide me a link where it has been discussed in detail?
     
  7. Oct 29, 2015 #6

    Henryk

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    I'm a physicist, I just know it.
     
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