How to deduce Gauss' law from Gauss Divergence Law

In summary, Gauss' Law and Gauss Divergence Law are two related mathematical laws used to understand the behavior of electric fields. While Gauss' Law can be derived from Gauss Divergence Law, it is important to account for singularities in the electric field strength when using spherical coordinates. The volume integral of div E [application of Gauss' theorem to Gauss' law) is proportional to Q, the total charge included, which is also equal to the volume integral of the charge density. This leads to the conclusion that the integrands of both sides must be equal, giving div E = densit/eps_0.
  • #1
nenyan
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Homework Statement


Gauss Divergence Law:
df53cbd418aaded3f2ad2d2fe1d60f2d.png

Gauss' law
914f57946de3c30d15e1a9778b276842.png


Can we obtain the Gauss' Law from Gauss Divergence Law?

Homework Equations



In Spherical coordinates,

electric field strength

(Q/4[itex]\pi[/itex]εr^2,0,0)
Then ∇[itex]\cdot[/itex]E=0+0+0=0

The Attempt at a Solution



We can not obtain the Gauss' Law from the general mathematical law?
 
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  • #2
So the volume integral of div E [application of Gauss' theorem to Gauss' law) is proportional to Q, the total charge included.

But Q is the volume integral of the charge density ... so we have a volume integral on both sides.

Then the integrands must be equal, which gives div E = densit/eps_0.
 
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  • #3
nenyan said:

Homework Statement


Gauss Divergence Law:
df53cbd418aaded3f2ad2d2fe1d60f2d.png

Gauss' law
914f57946de3c30d15e1a9778b276842.png


Can we obtain the Gauss' Law from Gauss Divergence Law?

Homework Equations



In Spherical coordinates,

electric field strength

(Q/4[itex]\pi[/itex]εr^2,0,0)
Then ∇[itex]\cdot[/itex]E=0+0+0=0

The Attempt at a Solution



We can not obtain the Gauss' Law from the general mathematical law?
There's a singularity in ##\vec{E}## at r=0 you need to account for.
 

1. What is Gauss' law and Gauss Divergence Law?

Gauss' law is a fundamental law in electromagnetism that relates the electric flux through a closed surface to the charge enclosed within the surface. Gauss Divergence Law, also known as the Divergence Theorem, is a mathematical theorem that relates the flux of a vector field through a closed surface to the divergence of the field within the surface.

2. Why is it important to deduce Gauss' law from Gauss Divergence Law?

Deducing Gauss' law from Gauss Divergence Law allows us to understand the fundamental relationship between the electric field and charge distribution in a given system. It also provides a powerful tool for solving complex electromagnetism problems.

3. What are the steps to deduce Gauss' law from Gauss Divergence Law?

The steps to deduce Gauss' law from Gauss Divergence Law are as follows: 1. Choose a Gaussian surface that encloses the charge distribution.2. Apply Gauss Divergence Law to the electric field and simplify using the properties of the divergence operator.3. Use the symmetry of the charge distribution to simplify the integral.4. Solve for the electric flux through the Gaussian surface.5. Equate the electric flux to the charge enclosed within the surface to obtain Gauss' law.

4. Can Gauss' law be used to calculate the electric field for any charge distribution?

Yes, Gauss' law can be used to calculate the electric field for any charge distribution as long as the charge distribution has sufficient symmetry to simplify the integral.

5. What are some practical applications of Gauss' law and Gauss Divergence Law?

Gauss' law and Gauss Divergence Law have various practical applications in the fields of electromagnetism, fluid mechanics, and heat transfer. They are used to calculate electric fields, magnetic fields, fluid flow, and heat transfer in various systems. They are also used in the design and analysis of electronic devices, such as capacitors and antennas.

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