Questions tagged [electromagnetic-radiation]
Propagating solutions to Maxwell’s equations in classical electromagnetism and real photons in quantum electrodynamics. A superset of thermal-radiation.
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What happens when a linear polarized EM wave encounters a perpendicular mesh of wires (which are electrically connected)?
Assume a radio wave with wavelength 1 m is traveling in the negative z direction when it encounters a grid of closely spaced wires (say, 10 cm separation) laying in the xy plane, with each wire ...
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Why is the intensity of a beam of light the squared magnitude of the phasor and not just the squared magnitude of the real part?
I'm learning about phasors and light intensity and there are two conflicting things I've been told that I can't reconcile.
Firstly I've been told that a phasor $e^{-ikz+i\phi}$ is a mathematical way ...
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How does parameters of the constitutive relation of electromagnetic media be constrained as for chiral, nonreciprocal or loss media?
The constitutive equations are:
$$
\bf D =\varepsilon E +\xi H \\
B =\mu H + \zeta E
$$
Why, when the media is nonreciprocal, the parameters $\xi$ and $\zeta$ only can take the real part equals zero,...
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Radiation from accelerated charged in a co-accelerated reference frame
I was wondering if I sit on a accelerated charge particle I will not observe radiation since the particle is at rest according to me. But my friend observes it from outside and he will see radiation ...
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Does Larmor radiation show that the fundamental laws are not necessarily time-reversible?
It is often said that the fundamental laws of physics are time-reversal symmetric, and therefore the arrow of time is an emergent phenomenon. An example that is often given is the elastic collision ...
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Radiation from a stationary charge relative to earth for a free falling observer
It is my understanding that if we have a charge at rest on earth, a free falling observer will see it radiating, as the charge is in an accelerated frame of reference. This observer can in principle ...
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Would we be able to see the superposition of two X-rays where the frequency of the modulation matches visible light?
Suppose I had the superposition of two electromagnetic waves whose angular frequency was in the X-ray region. Together they form a composite made of a carrier wave and a modulation wave where the ...
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When an element near the star surface absorbs the discrete frequency of star's em radiation do this absorbed photons ought to accumulate?
We all know about emittion lines that are empty from a discrete em freqency depending on the element that absorbs that frequency band near the star which we observe when looking at these astrophysical ...
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Single photon detection
Consider a thought experiment where we have a source emitting a single photon, like an atom/molecule going from an excited energy state to its ground state.
We have an infinite number of point ...
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What is the reletive permeability of structual steel?
Help, i need to know what the reletive permeability is of a few materials (listed below) but i can not find the data on the internet. Does annybody know the data or where i can find it?
-s235jr
-...
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Can an oscillatory field produced by a time-dependent charge distribution fall off faster than $1/r$?
An electric charge has a field that decays at large distances like $1/r^2$. A charge distribution with total charge zero, but with a nonvanishing dipole moment, has a field that decays at large ...
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Blackbody Radiation Simulation Software [closed]
I am trying to model the effective radiating temperatures of various three-dimensional solids (Tetrahedron, cube, octahedron, etc.) given a specific incident radiation. Are there any (free) softwares ...
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A question about circularly polarized light
At work, a senior colleague thinks that circularly polarized light does not exist. My problem is that we both work on a project involving polarized light. In some occasions, I would like to point out ...
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Why In an electromagnetic wave both electric and magnetic waves are in sync and perpendeculare? if one makes the other shouldnt there be a delay? [closed]
Why are electric and magnetic waves in phase if one induces the other? Shouldn't there be a delay, similar to how potential energy converts to kinetic energy and vice versa? Additionally, why are ...
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How are 3 Principle Sections possible in a crystal even when there is only one optical axis and all must contain it?
While studying polarization in calcite crystals, I came across that there are 3 possible principle sections in the rhombohedral crystal. But the conditions are that each section must be perpendicular ...
