Does a Charge on a Closed Surface Contribute to Electric Flux?

In summary, according to Gauss's Law, a charge on a closed surface does not create a nonzero flux through the surface as it is not considered to be enclosed by the surface.
  • #1
lugita15
1,554
15
According to Gauss's Law, the electric flux through a closed surface is equal to the charge enclosed by the surface divided by epsilon_0. This obviously excludes charges outside the surface. But what about *on* the surface? That is, it lies neither inside nor outside. Does this charge count as being "enclosed" in the sense of Gauss's Law? In other words, does the electric field of a charge "on" a closed surface create a nonzero flux through the surface?

Any help would be greatly appreciated.
Thank You in Advance.
 
Physics news on Phys.org
  • #2
lugita15 said:
According to Gauss's Law, the electric flux through a closed surface is equal to the charge enclosed by the surface divided by epsilon_0. This obviously excludes charges outside the surface. But what about *on* the surface? That is, it lies neither inside nor outside. Does this charge count as being "enclosed" in the sense of Gauss's Law? In other words, does the electric field of a charge "on" a closed surface create a nonzero flux through the surface?

Any help would be greatly appreciated.
Thank You in Advance.

I believe by definition all charge must be enclosed, therefore there is no surface charge.
 
  • #3
A Gaussian surface is a mathematical surface you decide on.
To apply Gauss's theorem, you must choose a surface that has charge either within or without, but not on your Gaussian surfce.
 
  • #4
If a charge was on the surface, the flux would be undefined at that point (since the field itself is undefined at the charge itself)
 

What is Gauss's Law?

Gauss's Law is a fundamental law in electromagnetism that relates the electric flux through a closed surface to the charge enclosed within that surface. It was first formulated by German mathematician and physicist Carl Friedrich Gauss.

How is Gauss's Law used in physics?

Gauss's Law is used to calculate the electric field generated by a charge distribution. It is also used to determine the amount of charge enclosed within a given surface, as well as to solve problems related to electric field and potential.

What is the mathematical formula for Gauss's Law?

The mathematical formula for Gauss's Law is ∮SE·dA = Qenc0, where ∮SE·dA represents the electric flux through a closed surface S, Qenc is the total charge enclosed by S, and ε0 is the permittivity of free space.

What are some real-world applications of Gauss's Law?

Gauss's Law has many practical applications, including determining the electric field inside a capacitor, calculating the electric field around a charged conductor, and analyzing the electric field of a point charge or a charged spherical shell.

What are the limitations of Gauss's Law?

Gauss's Law is only applicable to electrostatic situations, meaning that the charges must be at rest. It also assumes that the electric field is uniform over the surface being considered. Additionally, it does not take into account the effects of magnetic fields.

Similar threads

Replies
8
Views
815
Replies
1
Views
681
Replies
5
Views
2K
  • Electromagnetism
3
Replies
83
Views
3K
  • Classical Physics
Replies
2
Views
4K
  • Classical Physics
Replies
5
Views
2K
  • Introductory Physics Homework Help
Replies
12
Views
1K
  • Classical Physics
Replies
5
Views
1K
  • Introductory Physics Homework Help
Replies
10
Views
736
  • Introductory Physics Homework Help
Replies
11
Views
395
Back
Top