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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A question on a system of particles governed by laws of gravity and electromagnetic field
Consider a system of many point particles each having a certain mass and electric charge and certain initial velocity. This system is completely governed by the laws of gravitation and electromagnetic ...
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Quantizing EM field
Why when we quantize EM field, whe quantize the vector potential $A^\mu$ obtaining vectorial particles (photons) like the elastic field (phonons) and we can't quantize directly the EM-field tensor $F^{...
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My computer turns on when it "sees" me [closed]
Before asking, I swear that, for how it may seem strange, this is all true. Very briefly, when my pc is off and I am near it, it turns on. I do not touch anything. Nobody else have the same effect. I ...
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Energy conservation in Electrodynamics
Let us suppose that we have a known electromagnetic wave-train of finite size propagating in a certain direction. There is a probe charge on its way. This EMW is an external field for the charge. The ...
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Are inductance and self-inductance synonyms?
Wikipedia mentions that the word self in the word "self-inductance" is to differentiate it from "mutual inductance". But it does not state whether the two things are the same thing. So do the both ...
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1-form formulation of quantized electromagnetism
In a perpetual round of reformulations, I've put quantized electromagnetism into a 1-form notation. I'm looking for references that do anything similar, both to avoid reinventing the wheel and perhaps ...
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What is the difference between north and south magnetically?
Is there a reason that magnetic field lines are drawn from north to south or is this a purely arbitrarily defined protocol (for convenience)? Essentially what I am asking is: without a reference ...
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Electric field at a point being an $n^{th}$ derivative of electric (or magnetic) field at some other point
This is a theoretical question for which i would like to know an answer with an example.
I'd like to know if its possible to create a setup where the electric field at a point $P$ is $n^{th}$ ...
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Is it true that the angular momentum of electromagnetic waves in an anisotropic medium is an integral of motion?
Extending my previous question Angular moment and EM wave, does it make sense to talk about the angular momentum of electromagnetic waves in an anisotropic medium? It is not obvious that the angular ...
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Phase Accumulation of Hankel-waves upon propagation
Hankel functions are solutions to the scalar Helmholtz-equation $$\Delta\psi + k_e^2\psi = 0$$ in cylindrical and spherical geometry (with respect to a separated angular dependence). Thus, they are ...
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Moving conductors in magnetic fields: is there electric field or not?
this is my first question on PhysicsSE (I'm already an user of MathSE).
I'm a mathematics students trying to understand Faraday's law, that is
$$\varepsilon= -\frac{d \Phi_B}{dt}$$
where $\...
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Effect of a external EM field on a dielectric
If an external EM field (a laser, for example) act on a dielectric (a glass, for example) what will be the effect of this field on the dielectric constant and on the refractive index of the material? ...
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Making symmetry between E and B fields manifest in Lagrangian
Maxwell's equations are nearly symmetric between $E$ and $B$. If we add magnetic monopoles, or of course if we restrict ourselves to the sourceless case, then this symmetry is exact. This is not ...
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What is an "inclined magnetic field"?
What is meant by an "inclined magnetic field"? How is it different from the usual magnetic field?
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What direction does the force vector point in regards to Earth's E and B fields?
In regards to the right hand rule, given Earth's electric and magnetic field, in which "direction" would a particle go?