Questions tagged [electromagnetism]
The classical theory of electric and magnetic fields, both in the static and dynamic case. It also covers general questions about magnets, electric attraction/repulsion, etc. Distinct from electrical-engineering.
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How to explain this simple phenomenon from a moving frame?
Let us suppose we have an electron moving with velocity $\vec v$ as shown in the fig. as seen from the ground frame. We know that when it enters the region with uniform magnetic field it will follow a ...
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Explanation between the potential energy of a charge and the electric force experienced by a charge
Suppose there are two opposite charges and an infinite distance between the two. At this initial point, the electric potential energy of the two charges and the electric force experienced by each ...
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Maxwell's equations in electromagnetic theory [closed]
At M.Sc physics or BS physics level a student should study Maxwell's equations with how much depth tell name of specific concept
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Electromagnetsm, isospin, spin-1/2, and the early years of quantum mechanics question
An electron going around in a circular orbit produces a magnetic field because there is a varying electric field.
But the electric field of the electron itself is a spherically symmetrical field.
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Topic : Classical Electrodynamics; Lienard wiechert potentials [closed]
So I have just finished studying the Lienard wiechert potentials for a moving charged particle. After doing some problems from Griffiths I stumbled upon some problem which as follows:
An ...
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How to find permeability of a magnetic material?
I have been working with magnetic materials for quite some time now and never really explored this fundamental parameter. After looking through the literature I realize there and quite few different ...
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Why defects don't have an effective charge in metals?
In semiconductors and insulators, crystal defects, e.g., vacancies and interstitials, are treated as having an effective charge. In metals, however, defects are treated as neutral. I can expect that ...
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Ampere's law on solenoid, using a circular loop
Suppose we take a long and tightly wound solenoid with current I going in it. We can find the field inside, by ampere's law, taking a rectangular loop and assuming the magnetic field just outside the ...
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Field strength tensor written as commutator of covariant derivatives in QED
I am currently trying to understand the derivation of the relation
$$
\begin{equation}
F_{\mu\nu} = \frac{1}{iq}[D_{\mu}, D_{\nu}]\tag{1}\label{eq1}
\end{equation}
$$
in QED and I have trouble with ...
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Momentum of light in anisotropic media
This question is related to the Abraham-Minkowski controversy that has already been discussed extensively here and in the research community. But I want to ask about an aspect of this momentum ...
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Can you perfectly control electric currents' behavior in anisotropic media?
I'm an undergrad who is learning recently about anisotropy w.r.t. E&M. I understand that in anisotropic media the behavior of electric currents and other E&M aspects can be very unpredictable ...
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Concerning railguns and magnetic fields
I'm part of a group working on a Physics II project based on electromagnetism, and my group decided to create a proof-of-concept railgun, shown here:
https://doityourselfgadgets.com/2013/10/homemade-...
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How to use dipoles to enforce the boundary conditions for a spherical dielectric with complex permittivity
I want to impose an electric and magnetic field on a spherical dielectric of radius $ R $ and relative permittivity $\epsilon_r=\epsilon'+i\epsilon''$. Say the fields are slowly-varying (like a plane ...
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Diffraction when the wavefront is not parallel to the plane
I am studying Feynman's chapter on the origin of the index of the refractive index (see this link).
If I am not mistaken, what he does is to prove that when a wave enters a medium (modelled as a ...
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How and why does magnetic fields influence ferrous metals?
I know that a magnetic field is a result of moving charges (general relativity) but why and how would this positive charge (moving negative charge/electron -> less negative charge -> positive charge) ...
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