All Questions
Tagged with electromagnetism electromagnetic-radiation
1,800
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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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Is it possible for both electric and magnetic fields to have longitudinal component in a rectangular waveguide?
I know a rectangular waveguide cannot support TEM waves, but supports TE and TM waves. In the TE mode, $E_z=0$ and in the TM mode, $H_z=0$ (where propagation direction is along the $z$-axis). I want ...
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Confusion regarding phase
As far as I know about phase if the phase difference between two waves is positive, the former is leading..and the latter is lagging. Then why has D J Grifith stated this?
If the phase of the magnetic ...
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4
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Why should an electron falling into the nucleus, according to the Maxwell's laws of electrodynamics, destroy the atom?
It is often said in physics and chemistry classes and textbooks that atoms must be unstable when the electron continuously loses energy and finally fall into the nucleus according to classical physics....
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Can gravity radiate?
In electromagnetism, when a charge accelerates, it emits radiation. We know this because we can write the retarded potentials, apply $\vec E=- \nabla V-\frac{\partial \vec{A}}{\partial t}$ and $\vec B=...
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Confusion about EM spectrum and the Fourier transform
Since courses on signal analysis and electromagnetism I have become confused about what the spectrum of electromagnetic radiation really means. I know light is when electric and magnetic fields become ...
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Dipole radiation of a non-relativistic electron in elliptic motion [closed]
I'm trying to solve the following problem:
A non-relativistic electron is moving in elliptical motion inside a positively charged cylinder of homogenous charge density $\rho$. The initial radius ...
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3
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If quaternions are an extension of complex numbers, is there a study of EM wave theory in terms of quaternions?
I find that in standard textbooks and online resources, basic EM wave theory (such as radiation, plane wave solutions, polarization) is discussed by treating fields in terms of complex numbers. Is ...
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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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Is it possible to get an electromagnetic wave equation if the speed of light were infinite?
In an old question: How would night sky look like if the speed of light was infinite? the best answer was voted down to negative credits.
I cannot understand why. From Maxwell's equations, we derive ...
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How can a point source emit spherical EM waves when they are forbidden by Maxwell's equations?
I know that there exist plane wave solutions to the Maxwell equations in free space, and I tried solving them for a spherical wave emanating from a point but could find no solution consistent with the ...
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How could I calculate the strength of an electromagnetic field sufficient enough to generate plasma in low pressure argon gas?
For context, I wish to create a plasma toroid in a glass sphere of 25 Torr Argon gas like in the photo below; there are multiple examples of how to do this online using a class E oscillator ...
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Electromagnetic Field in a 3D Cavity with Lossy Boundary
I would like to find the electric and magnetic fields inside a cubic cavity with a lossy boundary (i.e. NOT a perfect conductor). I assume that the interior of the cavity is filled with a homogeneous ...
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Why does a group of charges with spherical symmetry, where each oscillates radially while retaining spherical symmetry, not radiate? [duplicate]
I am thinking about the problem, "Why does a group of charges with spherical symmetry, where each oscillates radially while retaining spherical symmetry, not radiate?" I figured out that ...
2
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Is energy contained in/transferred by light really discrete or is it continuous? [duplicate]
I don't really understand the wave-particle duality of light.I don't really understand the idea of photon, The idea of photon that is generally taught is that it is a fundamental unit of light with ...
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