What exactly is Electric Flux Density?

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SUMMARY

Electric flux density, represented as D, is defined by the equation D = εE, where ε is the permittivity of the medium and E is the electric field. The divergence of D, expressed as ∇·D, equals the charge density ρ. The symbol "phi" (Φ) represents electric flux, which is fundamentally different from D; they do not share the same units or represent the same physical concepts. The confusion arises from the historical use of the term "electric flux," but D quantifies electric field lines, while Φ quantifies the total electric field passing through a surface.

PREREQUISITES
  • Understanding of electromagnetic fields (EMF)
  • Familiarity with Maxwell's equations
  • Knowledge of electric permittivity (ε)
  • Basic grasp of vector calculus, specifically divergence
NEXT STEPS
  • Study the relationship between electric field (E) and electric flux density (D) in different media
  • Explore the historical context of electromagnetic terminology and its evolution
  • Learn about the applications of electric flux density in engineering and physics
  • Investigate the implications of charge density (ρ) in electromagnetic theory
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Students and professionals in physics and electrical engineering, particularly those focusing on electromagnetism and its applications in technology.

iVenky
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We define flux density as D= ε E right?
or even ∇.D=ρ

But I can't link the above with what is given in the wiki where they have used the symbol "phi"

http://en.wikipedia.org/wiki/Electric_flux


What is the difference between D and symbol "phi"?

I would be really happy if you could help me as I am new to EMF.

Thanks a lot. :)
 
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D and \Phi are nothing alike, don't have the same units, don't represent different aspects of the same quantity, nothing. That they share the words "electric flux" in them is simply misleading, but the roots of this terminology are historical, I'm sure.
 
What I read was D is the no of electric lines which seems to be same as \phi. What is the exact physical meaning of D ?

Thanks a lot.
 

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