Propagating solutions to Maxwell’s equations in classical electromagnetism and real photons in quantum electrodynamics. A superset of thermal-radiation.

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Can electromagnetic radiation be half-wave rectified in free space? [closed]

Electric field strength vs propagation direction of electromagnetic radiation(Wave Profile Comparison)
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does photon travels in a helical path in an optical vortex?

The wave front of the optical vortex beam is helical. Does it mean that the photon travels in a helical path? When the optical vortex beam is focused on a screen, an annular ring with dark center is ...
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55 views

If EM waves are not physical, positional waves (on a X,Y,Z axis), why does interference pattern appear positional?

I have read that EM waves propagate in straight lines: https://van.physics.illinois.edu/qa/listing.php?id=17699 Wherein the only the electric (E) and magnetic (B) fields to change (or oscillate) at ...
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How does light filtration work?

How exactly do certain types of glass filter out light within specific frequencies/wavelengths? I'm wondering because I read somewhere that certain types of windows filter out certain parts of the ...
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44 views

What is the least count of the timer clocks used in RADAR?

I was checking out some videos in YouTube regarding the working principle of RADAR. To quote some HOW IT WORKS: World War II Radar (720p), part 1, How does RADAR work? | James May Q&A | Head ...
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visualization of Radar waves [closed]

I'm fairly interested in broadening my understanding of Radar waves due to my interest in modern air warfare in which radars play a very central role. How would radar waves appear visually if they ...
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Is there a name for the squared refractive index?

In studying wave propagation through multilayers, the squared refractive index $n^2$ is a more pertinent parameter than $n$ itself. Is there a received name for $n^2$? Of course, as long as there is ...
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Why doesn't the motion of a car affect the frequency of radio stations?

When we go in a car and tune to an FM radio station, why doesn't our motion disturb the frequency? Like the Doppler effect?
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When align the neutron's magnetic dipole moment, does moving neutron radiates?

Was performed an experiment in the past, where neutrons pass a magnetic field and their magnetic dipole moment get aligned? Was measured an electromagnetic radiation during the experiment?
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45 views

Photograph of Light as Wave and Particle [duplicate]

what is this? actually its the first photo of light as wave and a particle. The bottom "slice" of the image shows the particles, while the top image shows light as a wave. i have questions 1.how ...
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69 views

Explanation of Interference of Electromagnetic Waves

There is a question on a test which goes like this: "Given two electromagnetic waves, one of wavelength 6.0 X 10-7 m and the other of wavelength 7.0 X 10-7 m, travelling in space. When the two ...
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88 views

Do EM waves need a medium to propagate? [duplicate]

The official theorie says that they don't need a medium, it states that: EM waves are a disturbance in the field First of all, what field?? An electromagnetic one ? I mean, I consider that field as ...
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Looking for full equation for radar cross section of corner reflector

There's a well-known formula for the RCS of a corner reflector (aka corner cube), to wit $ \sigma \varpropto \frac{L^4}{\lambda^2} $ . I've found several sources which cheerfully say "...valid for $ ...
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What can change a photon's frequency?

I found this question: Is it possible to apply force to a light particle? As it states, gravity can change the frequency of light by changing its momentum. My question regards other phenomena that ...
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How do you calculate the magnitude of the light waves emitted from an LED?

Question is in the title. My goal is to see if this is enough to make an interferometer using a surface-mount photodetector.
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Do rainbows have ultraviolet bands and infrared bands?

We have seen that rainbows looks so colorful as we are only able to see only the visible light. But Do they also have ultraviolet bands and infra-red bands, that we are unable to see? I know someone ...
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Are the EM waves that result from each of these processes distinguishable? Phase of light upon emission

In case 1, you have a single source of light that you pass through a diagonally oriented linear polarizer and then a half waveplate, such that the horizontal and vertical components become $\pi$ out ...
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My microwave oven disrupts my bluetooth connection even when I'm 12ft away. Should I be worried? [duplicate]

I often wear bluetooth headphones that connect to my mobile phone. I work on my laptop in my dining room approx. 12ft away from the microwave oven and my mobile phone is usually in my pocket; ...
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38 views

ionising atom(s) with gamma rays

if a gamma ray hits an electron and transfers energy, does it hit that electron (ionising the atom), transfer all its energy and stop or does it pass through multiple electrons, transferring a portion ...
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Would passing horizontally polarized light through a varying width vertical slit allow you to measure the positional (x) amplitude of light? [duplicate]

I have found closely related questions on StackExchange, but (surprisingly) not this exact question. Seems some answers say individual photons do not have amplitude, only when traveling with other ...
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1answer
72 views

How to create a vaccum tube & produce electron beam

I know that when an anode & cathode are placed inside a vaccum tube, electrons are emmited from cathode and goes towards anode. So, How to produce such a high voltage?, How to create such a ...
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55 views

If EM waves are made of oscillating electric and magnetic fields, how come photons have no charge?

I just recently learned that electromagnetic waves are made of oscillating electric and magnetic fields, and I have a question. In the standard model, photons are described as having zero charge, and ...
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37 views

Plane Mirror as the Screen in Young's experient

If I place a plane mirror instead of the screen in the Young's double slit experiment, what will I see? Will the bands appear on the mirror face?
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Is this a standing or moving wave?

The electric field of a uniform plane wave traveling in a source free region of free space is given by: $ \vec E= (0.5j \vec x + \vec y)(e^{j \beta z} - e^{-j \beta z})$. Is this a traveling wave or ...
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76 views

Propagating higher order Hermite Gaussian modes. What are complex amplitude coefficients?

I've been tasked with writing a code (in MatLab, but I'm currently using Mathematica because I don't know MatLab %\ ...) to simulate the propagation of a Gaussian beam. I don't really know anything ...
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76 views

Is it possible to produce coherent light with a thermal source? [closed]

Coherent light means monochromatic light and alle waves have the same phase difference. This is given for laser, where the resonator is a potential box and the outgoing waves have the same phase ...
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36 views

Why does a good conductor shows pronounced skin effect?

I am currently studying transmission of em waves and skin effect is puzzling me. Let us consider an em wave propogating in z-direction with electric field in x-direction & magnetic field in ...
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What does it mean to perturb the electromagnetic energy with respect to a change in a Lorentz frame?

I am perturbing the energy of an electromagnetic field using \begin{align} \dfrac{\partial U}{\partial \zeta} = \dfrac{1}{\mu} \boldsymbol{H}\cdot \dfrac{\partial \boldsymbol{H}}{\partial \zeta} + ...
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Inhomogeneous scattering from a dielectric box in 2D?

I wrote an E&M simulator and need to verify the accuracy. My simulator evaluates a 2D grid (which is what my camera measures), and would like to test an object that is minimally perturbed by ...
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Do rainbow shows spectral lines?

A spectral line is the electromagnetic radiation emitted when the electron jumps from higher orbital to a lower orbital of an atom. Water mainly consists of two elements namely hydrogen and oxygen, ...
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70 views

Can Maxwell's Equations explain electromagnetic radiation emission in an atom?

Can Maxwell's equations be used to explain the process of spontaneous emission when an electron drops from a higher energy level to a lower energy level? According the Maxwell equations, a changing ...
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1answer
94 views

Is it true that the self-force prevents a classical particle from falling into a Coulomb potential? What is the physical explanation of this result? [closed]

In 1943 CJ Eliezer published a paper claiming that the self-force prevents a zero angular momentum particle from ever reaching the center of an attractive Coulomb potential (and what's more that it ...
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Against what force are we doing work when we accelerate an electron?

In vol. I, chapter 32, of The Feynman Lectures, Feynman says: If we take a charged body and accelerate it up and down it radiates energy; if it were not charged it would not radiate energy. It ...
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Do the electric and magnetic components of an electromagnetic wave really generate each other?

Frequently when EM waves are taught, it is said that the change in electric field causes a change in the magnetic field, which then causes a change in the electric field, and so on and so forth. But ...
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62 views

What is space charge and how to calculate it?

I want to clarify the meaning of space charge. What I know is that the space charge is the total charge in a small region in space. I really confuse this in the ion beam context. Many text book says ...
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2answers
100 views

Is light a particle with EMF or does it travel in wave? [duplicate]

Is light a particle which has a electromagnetic field around it OR does the particle itself travels in a wave like motion? IS it just the EM field which moves in a wavy motion like ripples? (Please ...
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44 views

How would one build an RF cavity?

How does an RF cavity, such as the RF cavities in the LHC, work mechanically and mathematically? How would one build an RF cavity? What equations govern the speed of a charged particle in an RF ...
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How does electromagnetic radiation affect the velocity of a charged particle?

I've heard that the acceleration of a charged particle releases electromagnetic waves. So let's say there is a charged electron moving forwards in a region with a downwards magnetic field. If the ...
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60 views

Has someone measured that in the far field of radio waves, the electric and magnetic field oscillate synchronously?

That in near field both fields oscillating 90° displaced is obvious since in antenna rod a lot of electrons will be accelerated and and this oscillation of electric field is escorted by alignment of ...
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31 views

Polarization of light for a fast moving observer

For a fast moving observer the frequency of light becomes shifted due to the (relativistic) Doppler effect. But what about the polarization of the light? Could it be, that e.g. circular polarized ...
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2answers
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For a light of given frequency, what does the amount of refraction in a variable medium depends upon?

I want to know whether the amount of refraction of a given monochromatic light depends solely upon the density of the of the medium ( increase the density to increase the angle of refraction), or ...
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Is my window's semi-transparency a consequence of elementary quantum mechanics? [duplicate]

Studying mathematical concepts of quantum mechanics, I have recently become familiar with the classical model of one-dimensional particle being scattered by a potential barrier. As a mathematician, I ...
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1answer
46 views

Amplitude of eliptically polarised light

In elliptically polarized light, can one define something called amplitude of Electric field? If yes, how do we determine it?
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1answer
70 views

Have we really measured the wavelength of light? [duplicate]

Have we practically measured the distances between the variations of electromagnetic radiations in space in nanometers or is it just theoritical because of calculations? Also the one who have marked ...
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What does electric field of unpolarized light look like when measured?

When we talk about fermions in mixed state, we say that their state can't be described by a wavefunction and just compute all the probabilities using density matrix. That's OK because the ...
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1answer
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Can a magnifying glass work on EM radiation other than visible light?

A magnifying glass is a convex lens which allows us to bend visible light, thus the image of the object appears larger. My question is, can a magnifying glass work on the rest of the electromagnetic ...
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4answers
168 views

Why aren't we affected by radium?

1)We have radium clocks, watches, wrist bands and many things which glow because of radium but we know that radium is radioactive so why isn't it harmfull for us when in bands, watches etc. 2)Does it ...
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32 views

Microwave burns related to power per photon?

In wireless telecomunications we have multiple bandwidths being used nowadays: GSM 900Mhz and 1800Mhz, UMTS 2100Mhz, LTE 800Mhz, 1800Mhz and 2600Mhz, Wi-Fi 2.4Ghz and 5Ghz, (reffering to European ...
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138 views

If we go to space why isn't the temperature high? [duplicate]

We know that the temperature in space (which has vacuum) is low. If I go to space will I feel sweaty and hot or chilly? I think I will feel sweaty and hot because the radiation (UV, IR, etc) of the ...