All Questions
Tagged with electromagnetic-radiation waves
814
questions
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Is there an IR-camera-detectible color that can be the coat for a material to transfer the material heat by emitting into the space? [closed]
If we see a material it is coloured in a color that our brain could easly recognize. But when we look at it by the help of an IR camera it could also be coloured and if two materials have same ...
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2
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123
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Diffraction when the wavefront is not parallel to the plane
I am studying Feynman's chapter on the origin of the index of the refractive index (see this link).
If I am not mistaken, what he does is to prove that when a wave enters a medium (modelled as a ...
- 2,697
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Direction of propagation of extraordinary wave inside a birefringent medium
I am reading Optics by Ajoy Ghatak, in which the author explains the phenomenon of double refraction in a calcite crystal using Huygens' principle. My query is in the analysis of the case of normal ...
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What actually happens when light goes into a waveguide?
I have only dealt with a rudimentary theoretical treatment of how light propagates inside a waveguide, such as those available in Griffiths.
One thing bugging me is that I still do not know how ...
- 692
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Why does radiation of small wavelength interact with small objects?
I was reading chapter 2 from the book 'Diagnostic Radiology Physics : A handbook for Students and Teachers', and came across the following quote
"X rays of energy of a few tens of ...
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How to compute the diffraction efficiency of a thin phase grating with arbitrary groove shape?
From Magnusson and Gaylord (1978), the wave amplitudes, $S_i(z)$, of $p$-polarized light for a thin, arbitrary phase grating are given by the equation
$$
\frac{\partial S_i}{\partial z} + \gamma \sum_{...
- 123
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2
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Why are electromagnetic waves inverted when reflected at a fast to slow medium boundary?
I've been taught before that mechanical waves, when they hit a boundary between a less dense (faster) medium and a more dense (slower) medium, the reflected wave is inverted because it acts like a ...
- 12.2k
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Why is the Poynting flux not conserved across the interface between two conducting materials?
This question is part of my attempt to use an answer to another question I've posted on this site.
If I have two materials with complex indices of refraction, $\widetilde{n}_0$ and $\widetilde{n}_1$, ...
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1
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745
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What is the physical meaning of the complex field amplitude?
I see that the harmonic field is sometimes written in exponential form. But sometimes the complex amplitude of this form is just a constant and in others (like when talking about modes) is dependent ...
CommunityBot
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2
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Is there a way to use the optical transfer-matrix method to determine the absorbance of each layer in a multilayer stack?
I've implemented the transfer-matrix method to determine the the transmittance and reflectance of a multilayer stack of thin films.
I know that (ignoring scattering) the absorbance of the entire stack ...
- 171
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319
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Why is this question indicating a Fraunhofer Region rather than Fresnel Region?
I was thinking that because the source plane is infinitely large would be analogous to having the source plane being infinitely close, which would imply a Fresnel region rather than Fraunhofer.
...
CommunityBot
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Can Amps be used as a unit of measure for the amplitude of an EM wave?
As far as I know the definition for the amplitude of a wave is the distance between the line $y=0$ and the peak of the wave which in most cases is going to be a unit of length. I also understand that ...
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3
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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 ...
- 324
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Induced charge density on perfect conductor
Assuming there is a perfect conductor at $x=0$ in $\mathbb{R}^3$ and a plane EM wave $\vec{E}_i(\vec{x},t)=\vec{E_i^0}e^{i(kx-\omega t)}$ is coming from $x=- \infty$. We know, that the wave $\vec{E_r}(...
CommunityBot
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Spherical laser beam terminology
I am currently seeking the correct terminology for a beam that expands linearly from a fixed point, resulting in its wavefronts forming spherical surfaces. However, the beam does not expand in all ...
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