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0 votes
2 answers
510 views

Gauss divergence theorem (GDT) in physics

Some of the statements for $GDT$ which I find in modern textbooks (both electromagnetism and multivariable calculus textbooks) are: (1) Calculus: Several variables Adams Let $D$ be a regular, ...
Oliver's user avatar
  • 11
2 votes
1 answer
353 views

Will the flux through an arbitrary closed surface be finite or infinite when a plane charge intersects the Gaussian surface?

Let's consider a closed Gaussian surface (in red). The white line and the white shaded part lies inside the Gaussian surface and the black line and the portion above it lies outside the Gaussian ...
lorilori's user avatar
  • 176
3 votes
1 answer
294 views

Formal Connection Between Symmetry and Gauss's Law

In the standard undergraduate treatment of E&M, Gauss's Law is loosely stated as "the electric flux through a closed surface is proportional to the enclosed charge". Equivalently, in differential ...
TheMac's user avatar
  • 130
2 votes
0 answers
69 views

Is the gravitational field $\mathbf{g}(x)=-G\int_{\Bbb R^3}\rho(y)\frac{x-y}{|x-y|^3}\,\mathrm{d}y$ continuously differentiable?

I apologize for mathematician-style question, but I was wondering if for continuous mass density $\rho:\Bbb R^3\to\Bbb R$ with compact support, the gravitational field $$\mathbf{g}(x)=-G\int_{\Bbb R^3}...
Dominic Wynter's user avatar
8 votes
2 answers
583 views

Calculating the potential on a surface from the potential on another surface

The question is short: If a charge (or mass) distribution $\rho$ is enclosed by surface $S_1$, I can calculate the electrostatic (or gravitational) potential on that surface by integrating $\rho(r') \ ...
uhoh's user avatar
  • 6,273
2 votes
1 answer
1k views

Divergence of Electric Field: Moving Del Operator Inside Integral

I'm reading Griffiths E&M book (4th edition), and on page 71 he starts with the expression for the electric field of a volume charge distribution: $$ \vec{E}(\vec{r}) = \frac{1}{4\pi \epsilon_0}\...
Mike Bell's user avatar
  • 758
9 votes
1 answer
847 views

Is there a "more rigorous" derivation of the electrostatic boundary conditions?

When I first saw a derivation of the electrostatic boundary conditions it wasn't quite rigorous. It was essentially the argument used by Griffiths in his book: Suppose we draw a wafer-thin Gaussian ...
Gold's user avatar
  • 36.4k
3 votes
1 answer
537 views

Divergence Theorem, mathematical approach to Gauss's Law?

Let $D$ be a compact region in $\mathbb{R}^3$ with a smooth boundary $S$. Assume $0 \in \text{Int}(D)$. If an electric charge of magnitude $q$ is placed at $0$, the resulting force field is $q\vec{r}/...
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