Questions tagged [gauss-law]
A law in classical electromagnetism and Newtonian gravity which relates (charge) density to the divergence of a field, or alternatively the charge in a volume to the flux through the bounding surface.
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Can someone give an intuitive way of understanding why Gauss's law holds?
Gauss' Law of electrostatics is an amazing law. It is extremely useful (as far as problems framed for it are concerned :D. I do not have a real world-problem solving experience of using Gauss' Law).
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Electric Field of Hollow Cylinder
Let's say we have a hollow cylinder with a charge $q$, radius $r$ and height $h$ as in the figure below.
I am trying to find the electric field perpendicular to the surface of the hollow cylinder. I ...
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Flux received by a negative charge
Consider two charges $+q$ and $-Q$ placed at a distance, note charge $q$ and $Q$ are different in terms of magnitude.
My question: is number of flux lines received by $-Q$ proportional to its own ...
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Is there something similar to Gauss's Law For Gravity in General Relativity?
In Newtonian Physics there is an equation that for the Gravitational Flux of an object known as Gauss's Law For Gravity. Gauss's Law for Gravity describes the number of Gravitational Field Lines ...
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Electric Field "at" the surface of a conductor
It has been pointed out to me that the Electric field exactly on the surface of the conductor is conventionally taken to be $E=\frac{\sigma}{2\epsilon_0}$; does this come from taking the midpoint of ...
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Why does Gauss's law for magnetism imply existence of a magnetic vector potential?
Gauss's law for magnetism is $\vec{\nabla} \cdot \vec{B} = 0$, and I read that this implies we can write $\vec{B} = \vec{\nabla} \times \vec{A}$, for some vector potential $\vec{A}$.
I understand that ...
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Why is electric flux defined as $\Phi = E \cdot S$?
Flux, as I understand it, is the amount of substance passing through a particular surface over some time. So, from a simple perspective, considering photons that go through some virtual surface $A$ (...
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Why do magnetic field lines behave the way they do?
I learned that the bar magnet makes a magnetic field and the field lines have a certain shape which kind of resembles two semiovals.
And if we pass current through a conductor then it makes a ...
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Why does the electric field of an infinite line depend on the distance, but not on an infinite plane?
I understand that with an infinite plane, as you get closer, the infinitesimal contributions to the electric field become greater in module. The direction of the vectors become less perpendicular to ...
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Is Gauss' law valid for time-dependent electric fields?
The Maxwell's equation $\boldsymbol{\nabla}\cdot \textbf{E}(\textbf{r})=\frac{\rho(\textbf{r})}{\epsilon_0}$ is derived from the Gauss law in electrostatics (which is in turn derived from Coulomb's ...
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Why charges reside on the surface on conductor? [duplicate]
In a hollow conductor and in a spherical shell the charges reside on its surface and there is no electric field inside it.Please tell me the reason behind it.
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Charge inside a charged spherical shell
If I were to put a negative charge inside a negatively charged spherical shell, will it move to the center?
Electric field inside the shell due to the shell is zero (Gauss's Law), would that mean the ...
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Factor of 4 (or 2) in the gravitoelectromagnetic (GEM) Lorentz-force law. Which is correct? Why is it there?
I realize that the Gravitoelectromagnetic equations (GEM) are derived from the Einstein field equation (EFE) in the degenerate case of reasonably flat spacetime, which is the case for the propagation ...
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Why can't an electric field line suddenly break?
My book has the following question in it as an exercise:
An electrostatic field line is a continuous curve i.e. a field line cannot have sudden breaks. Why not?
I cannot seem to be able to reason ...
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Why are there no charges inside a conducting sphere?
Why is it necessarily true that all charges occupy themselves only on the surface of a conducting sphere, and not anywhere inside the sphere? One argument is that if a charge were to be inside a ...
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