Need Help Understanding Electric Flux and Electric Flux Density

AI Thread Summary
Electric flux is defined as the flow of a vector field E through a surface dS, represented by the equation E·dS, which indicates the quantity passing through that surface. The surface density of this flux is given by E·n, where n is the surface orientation. Electric flux density, often denoted as D, is distinct from electric field E, as it incorporates the effects of free and bound charges in a material. The discussion also touches on magnetic flux density, represented by B, suggesting a parallel in terminology. Clarification on these concepts is sought to better understand their differences and applications.
Shreya
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Homework Statement
What is Electric Flux?
What is the difference between Electric Flux and electric flux density?
Relevant Equations
Electric Flux = E*ds cos (theta)
I don't understand the exact meaning of flux.
Please be kind to help.
 
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Have you ever computed the flux of any vector field?
 
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The relevant equation
\mathbf{E}\cdot\mathbf{dS}
is a definition of flux or flow of vector field E on surface dS. It is interpreted as a quantity flow passing through surface ##\mathbf{dS}=\mathbf{n} dS##.
Its (surface) density is \frac{\mathbf{E}\cdot\mathbf{dS}}{dS}=\mathbf{E}\cdot\mathbf{n}
which requires orientation of the surface.
 
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Gordianus said:
Have you ever computed the flux of any vector field?
No, but I learned abt Volume flux as volume passing through an area per unit time
 
anuttarasammyak said:
The relevant equation
\mathbf{E}\cdot\mathbf{dS}
is a definition of flux or flow of vector field E on surface dS. It is interpreted as a quantity flow passing through surface ##\mathbf{dS}=\mathbf{n} dS##.
Its (surface) density is \frac{\mathbf{E}\cdot\mathbf{dS}}{dS}=\mathbf{E}\cdot\mathbf{n}
which requires orientation of the surface.
Thanks a lot!
Can you please explain the difference between electric flux and electric flux density?
Is electric flux density = electric field ?
Please help
 
Shreya said:
Is electric flux density = electric field ?
The last line of post #3 is electric flux density for given infinite area ##\mathbf{dS}##.

Electric displacement field ##\mathbf{D}## is (was ?) called electric flux density but is something different from the above mathematics. Along the same discussion I wonder magnetic flux density is proper as one of the names of ##\mathbf{B}##. I should appreciate the advice of senior learners.
 
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Got this image from a source: I think it confirms what anuttarasammyk has said, Thank
You!
 

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