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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Accelerating Expansion of Universe - Why Not Caused by Radiation?
As I understand it, dark matter and dark energy are used as an 'explanation' for how universe expansion is accelerating; because without it gravity would be expected to cause a long term shrinking.
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What is the solar radiative power on a clear sky day through a surface which is parallel to the sun's incidence on Earth?
Assuming that the solar power through the incident surface is known. How can we calculate or estimate the radiation through the parallel surface assuming a clear sky?
Looking for watts per square ...
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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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Stars that have fairly high gravitational redshift and calculation of their surface temperature by Planck emition spectra?
How high can the ratio between gravitational redshift and planck emition spectra be depending on the mass of the star so by how much this gravitational redshift could elongate the Planck spectra of ...
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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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What is light? how is it connected to electromagnetic radiation?
I am trying to understand how light works and electromagnetic radiation, from what I understand charges cause disturbances in electric fields, which triggers a magnetic field, and then the back and ...
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Cross section along the single transmission path of electron
I am studying this research paper "Forecasting of ionospheric vertical total electron content (TEC) using LSTM networks" about ionosphere, but in introduction section I phrase I didn't ...
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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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How many photons are received per bit transmitted from Voyager 1?
As of 2024, according to https://voyager.jpl.nasa.gov/ , Voyager 1 is around one light·day away from Earth and still in radio contact. When Voyager 1 sends messages to Earth, roughly how many photons ...
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Is it impossible to construct a Faraday cage that can block a *static* electric field?
I think the answer is yes. My reasoning is this: Imagine for argument's sake, we could have a charged negative source that has its field blocked by a Faraday cage. We can transport a positive charge ...
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Distance needed for visible light to be cosmologically redshifted to microwave
What distance will it take for visible light to become a microwave due to cosmological redshift?
I'm not sure how to calculate this, as I'm never good at complex math. I tried googling but didn't find ...
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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 ...
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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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