Is There a Constant Parallel to ε0 in Gauss's Law in cgs?

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The discussion centers on the relationship between permittivity (ε0) in the SI system and its equivalent in the cgs system within the context of Gauss's Law. It highlights that in the cgs system, Coulomb's law simplifies to F = qq'/r² without the ε0 factor, indicating that ε0 is effectively equal to 1 in cgs. The participants clarify that the term 1/4π is necessary in the SI system to ensure consistency with the area of a sphere when applying Gauss's Law. The integral for Gauss's Law is mentioned, emphasizing the need for understanding the electric field around a point charge. Overall, the discussion confirms that while the formulations differ, the underlying principles remain consistent across the two systems.
Karol
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Homework Statement


Is there a constant parrallel to the ε0 permittivity in the Gauss law in c.g.s?

Homework Equations


Coulomb force in m.k.s: ##F=\frac{1}{4\pi\varepsilon_0}\frac{qq'}{r^2}##
Coulomb force in c.g.s: ##F=\frac{qq'}{r^2}##
Gauss's law in m.k.s: ##\frac{N}{A}=\varepsilon_0 E##

The Attempt at a Solution


The Coulomb's constant k was transformed to ##\frac{1}{4\pi\varepsilon_0}## in order that the number of field lines N extruding from a surpace round a point charge will equal the net chrage inside the surface:
\frac{N}{A}=\varepsilon_0 E\rightarrow \frac{N}{4\pi r^2}=\varepsilon_0 \frac{q}{4\pi\varepsilon_0 r^2}\rightarrow N=q
So the ##\frac{1}{4\pi}## term was chosen for that in order to cancel with the area of a sphere.
I think, in order that N=q will be also in c.g.s we also need ##\frac{1}{4\pi}## term:
Coulomb's law in c.g.s: ##F=\frac{1}{4\pi B}\frac{qq'}{r^2}\rightarrow \frac{1}{4\pi B}=1##
 
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In the cgs system, the Coulomb force is ##F=\frac{q_1 q_2}{r^2} ##,
ε0=1, D=εE in materials, D=E in vacuum.
Gauss' Law for a single point charge in vacuum ##\oint{E_n dA} = 4\pi q_{enclosed}##
 
I don't know yet this integral.
So i am right, right? Coulomb's law in c.g.s: ##F=\frac{1}{4\pi}\frac{qq'}{r^2}##
 
Karol said:
I don't know yet this integral.
So i am right, right? Coulomb's law in c.g.s: ##F=\frac{1}{4\pi}\frac{qq'}{r^2}##
No. ##F=\frac{qq'}{r^2}##
The electric field around a point charge q is radial, and the magnitude is E=q/r2. Integrating is to a sphere of radius r, with the charge in the centre is (4πr2)E = 4πq
 
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