Why Do Different Sources Show Varying Electric Flux Equations?

[Jimmy84]

Homework Statement

Im starting to read about the electric flux and gauss's law. I am reading two books, Serway and Schaums electromagnetics.

The weird thing is that I'm getting different equations for the electric flux

Serway says that the Electric flux ψ is ∫E ds = 1/ε ∫ρ dv = Q/ε

While in other books I found that The Electric flux ψ is ∫ρ dv = Q

What is the real Electric flux equation ?

Thanks a lot.

Homework Equations

The Attempt at a Solution

 

[TSny]

In Schaum's, is the flux ψ defined in terms of the field E or the field D?

 

[Jimmy84]

In Schaum's, is the flux ψ defined in terms of the field E or the field D?

it is defined in terms of D

as ∫D ds = Q = ψ

 

[TSny]

Ok, that should account for the difference if you look at the relationship between E and D.