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Why is D called the "electric flux density vector"?
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Thanks guys. Now I know.
BTW, is there something wrong with calling D the "electric field strength" (just like we call H the "magnetic field strength")?
More on whether to call H or B the magnetic field:.. because E and B are the fundamental field quantities, while D and H are derived [Jackson] "as a matter of convenience to take into account in an average way the contributions ... of atomic charges and currents." That is why E and B should be called fields, and why Mel Schwartz doesn't bother to even name H in his book. Furthermore, D is almost universally called Electric Displacement, and only rarely "dielectric flux density."
A survey of E&M books on my shelf shows B is called
Magnetic Induction -- by Smythe, Stratton, Jackson, Reitz & Milford
Magnetic Field -- Schwartz, Weber
alternately
Magnetic Flux Density -- Weber, Jackson
H is called
Magnetic Field or Field Intensity -- Smythe, Stratton, Jackson
Magnetic Intensity -- Weber, Reitz & Milford
unnamed -- Schwartz
Wow! I didn't know that such a simple question would have such an interesting answer!
BTW, robphy the way you describe E, H, B, & D as geometric objects with "one/two-form;" what branch of mathematics would you need to study in order to become familiar with these types of terminologies?
tensor calculus and differential geometry.
consult the references I linked in my previous post
Your units for D and B are for flux densities.E and H are fields. (V/m, A/m)
D and B are fluxes. (C/m^2, Wb/m^2)
You might do better with "Classical Electromagnetism" by Franklin which answers your question in chapter 6.So my question is what is the physical meaning of vectors P, M, D and H? Also, what is the point of the permittivity number if it just cancels with that in the denominator of Coulomb’s constant when multiplying it with E? Someone please help show me where I’m going wrong.