All Questions
Tagged with electromagnetism homework-and-exercises
1,552
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Equivalent form of Bianchi identity in electromagnetism
In electromagnetism, we can write the Bianchi identity in terms of the field strength tensor $F_{\mu \nu}$ as,
$$ \partial_{\lambda} F_{\mu \nu} + \partial_{\mu} F_{\nu \lambda}+ \partial_{\nu} F_{\...
- 1,751
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Energy-Momentum Tensor for Electromagnetism in Curved Space
$\newcommand{\l}{\mathcal L} \newcommand{\g}{\sqrt{-g}}$$\newcommand{\fdv}[2]{\frac{\delta #1}{\delta #2}}$I want to calculate the energy-momentum tensor in curved free space by functional ...
- 4,021
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Make a semi transparent mirror with copper
The question:
How would you make a semi transparent mirror (50% reflection, 50% transmission) with glass with a layer of copper. For light $\lambda$ = 500nm Try to be as realistic as possible
What I'...
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Rotating bar magnet : current induced in circuit
I don't think this problem makes sense. The answer given is (a). Aren't the field lines parallel to the loop, what does rotation affect ? create atomic currents?
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Derivative of the electromagnetic tensor invariant $F_{\mu\nu}F^{\mu\nu}$
The electromagnetic field tensor is $F_{\mu\nu}=\partial_\mu A_\nu - \partial_\nu A_\mu$. I am trying to calculate the quantity
$$ \frac{\partial(F_{\alpha\beta}F^{\alpha\beta})}{\partial(\partial_{\...
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Why do these calculations of EM fields for a magnet and wire loop seem inconsistent?
Suppose you have a conducting circular wire loop and a magnet moving towards each other. They move along the $z$ direction with nonrelativistic constant speed $v$. Let the $B$ field of the magnet in ...
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Flux linkage inside of a conductor
Can someone explain to me why the flux linkage inside of a conductor is dependent on the cross sectional area of the conductor?
My book says that d$\lambda$ = $(x/r)^2\phi$ where $\phi$ is the ...
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Aharonov-Bohm Effect in Torus
I had a very brief introduction to the Aharonov-Bohm effect in class. The lecturer introduced the notion that $H(\Phi=\Phi_0)$ and $H(\Phi=0)$ gives identical energy spectrum and that the Hamiltonians ...
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Force on Earth due to Sun's radiation pressure
I have been asked by my Classical Electrodynamics professor to calculate the force that the Sun exerts in the Earth's surface due to its radiation pressure supposing that all radiation is absorbed and ...
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Paradox in special relativity involving capacitor
In the laboratory reference frame (LRF), a horizontally moving (with constant speed) flat capacitor would have a different size of plates therefore resulting in different capacity $C'$, namely
$$
C' = ...
- 411
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Confusion in Maxwell's derivation of Ampere's Force Law - Part II [closed]
I am reading Maxwell's "a treatise on electricity and magnetism, Volume 2, page 156" about "Ampere's Force Law". I have some confusion in the following pages:
My question is of two parts:
1. ...
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Acceleration in relativistic particle [closed]
Suppose that a relativistic particle of mass at rest $m_0$ and charge $q$ moves under the influence $F$. Show that the acceleration $a$ of the particle can be expressed as follows:
$$a = \frac1mF + \...
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Shouldn't the electric field in a solid insulating sphere be linear with radius?
I am a senior in High School who is taking the course AP Physics Electricity and Magnetism.
I was studying Gauss's laws and I found this problem:
A solid insulating sphere of radius R contains a ...
5
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Two balls are dropped from the same height. Ball A is metallic and B, made up of an insulating material. Which of them touches ground first? [closed]
General motion under gravity states that both of them reach the ground simultaneously. But here, ball B reaches first. I searched for the solution but couldn't find any. Does it have anything to do ...
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