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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Motion of a magnet inside a solenoid
I have a homework problem where a bar magnet is placed halfway inside a horizontal solenoid. A cut away shows that the magnet's north pole points to the left of the page and the south pole is outside ...
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Conformal mapping and van der Pauw
I'm trying to understand the van der Pauw methods with my limited mathematical understanding. If any of my steps are wrong, please correct me.
As far as I understood from a textbook (Mahan, Gerald D. ...
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Maxwell stress tensor on a capacitor late given a dielectric
Given a capacitor with large plates (area $A$) separated by a dielectric with relative permittivity $\varepsilon_r$ and thickness $g$, I believe the Maxwell stress tensor states that the force on each ...
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How to derive magnetic moment for integrated circuit level?
Imagine we have a circuit on the xy-plane, with a random geometry (it just need to be closed). I want to calculate the magnetic moment of this setup:
$$\vec{m} = \frac{1}{2} \int_V d^3 x' \vec{x}' \...
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About the notation for TEM waves
I just came across this article where the term "$\mathrm{TE}_{101}$ microwave mode" is mentioned. Other than the basics of TEM waves which I learned in Griffiths, this is the first time I ...
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Seeking Advanced Study Guidance in Electromagnetism [closed]
I hope this post doesn't break any community rules, I've tried to look for such but couldn't find.
I am concluding my first undergraduate course in Electromagnetism next week. I am confident in my ...
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What's the coordinate of the Landau tube?
The Hamiltonian of a three-dimensional electron gas in a static magnetic field $\vec{B}$ is :
$$\hat{H}=\frac{(\hat{\vec{p}}+e\hat{\vec{A}})^2}{2m}$$
If choosing $\vec{B}=B\vec{e_z}$ and using Landau ...
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How is the index notation for the electromagnetic potentials defined?
I don't understand, how the $\vec{A}$ potential is defined in the covariant formulation of the Maxwell-Equations.
I am using the metric $(+,-,-,-)$.
The electric field (SI-Units) is defined as:
$$
\...
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Lenz law - Direction of induced current
I understand the Lenz Law is such that it tells us that the induced current must be in a direction that makes the end of the solenoid facing the magnet behave as a North Pole to repel the magnet’s ...
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How do I find the wavelength of an EM wave derived from an accelerating electron, given its acceleration?
I understand the Larmors formula, but I can't find any material regarding wavelength of a single photon.
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How to solve Relativistic Lorentz Force equation if $\gamma$ is not constant?
I am trying to numerically obtain the trajectory of an electron inside a periodic magnetic field $\mathbf{B}$, taking into account that the relativistic factor $\gamma$ is not a constant (the electron ...
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Motor Effect Experiment
I recently saw an demonstration (image below) where the motor effect was being shown. They used the fact that forces come in pairs (Newton's third law) and so when current goes through the copper rod, ...
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A question on perturbed flux function
Given a magnetic field $\mathbf{B}=B_{0}\left(\dfrac{xz}{z_{s}^{2}},\dfrac{yz}{z_{s}^{2}}, 1-2\left( \dfrac{x^{2}}{r_{s}^{2}}+\dfrac{y^{2}}{r_{s}^{2}}\right) -\dfrac{z^{2}}{z_{s}^{2}}\right)$ with the ...
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What is radial and axial component of magnetic induction of a coil? [closed]
I am sorry if my question is stupid, but can someone explain what are the radial and axial component of magnetic induction of a coil. I am reading an article about the magnetic field generated by coil....
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Materials to complement "Interacting Electrons and Quantum Magnetism" by Assa Auerbach
Does anyone know of any material, such as lecture notes from a university, that can complement the sometimes brief chapters of the book "Interacting Electrons and Quantum Magnetism" by Assa Auerbach?
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