Questions tagged [electromagnetism]
The classical theory of electric and magnetic fields, both in the static and dynamic case. It also covers general questions about magnets, electric attraction/repulsion, etc. Distinct from electrical-engineering.
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Modeling centrifugal distortion with an effective charge distribution
The hamiltonian of a rigid object with a totally symmetric moment of inertia (i.e. a "spherical top") will depend only on the magnitude of its angular momentum.
If we allow the object to ...
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Why the frequency component is not included when the energy of a wave is described?
Energy of a wave is directly proportional to its Amplitude squared. There is no inclusion of frequency in it. But by intuition if one thinks about it, isn't it obvious that a wave with higher ...
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Should a wire loop moving through a constant rectangular magnetic field directed perpendicular to it's motion have zero induced current in the middle?
Suppose we have a loop of copper wire moving perpendicularly through a constant finite rectangular magnetic field directed into the screen .
When the loop enters the field, the induced current would ...
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What is the difference between the induction of a magnetic field $B$ and the magnetic field strength $H$?
I just started learning about magnetic fields by myself. In my textbook it says that the magnitude or intensity of induction of a magnetic field is equal to the amount of field lines that pass through ...
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Magnetic Field Generation in a Vacuum Through Special Relativity
The way special relativity explains electromagnetism is that when electrons move, their lengths contract due to relativistic effects, even though they do not move at extremely high speeds. This ...
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Does electric and magnetic field from electromagnetic radiation are 2D based? [closed]
I'm getting into physics, specially in electromagnetism.
When we're talking about electromagnetic radiation. Does it has a 2D shape when it's propagating through space?
Does Maxwell's equations ...
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Field theories where the potential solves a linear Schrodinger equation
Are there physical situations/applications where the potential solves a linear time-dependent Schrodinger equation, or where the gradient of a solution to the Schrodinger equation (after somehow ...
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How to avoid the ordinary Coulomb solution in QCD?
To see where QCD starts to differ from the behavior of EM fields, we might begin by looking at the classical field. A search brings up
[question 339978] and [question 360061] but no answer is found ...
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How would I calculate plasma density profile for a plasma in a magnetic field?
I want to find the density profile of a xenon gas plasma at a given pressure.
My current approach is to model the plasma as a fluid and use the continuity equation below:
$\frac{\partial n(\vec{r},t)}{...
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Can Stern-Gerlach spin alignment be seen as a result of EM radiation of precessing magnetic dipole?
Stern-Gerlach experiment is often seen as idealization of measurement. Using strong magnetic field, it makes magnetic dipoles (of e.g. atoms) align in parallel or anti-parallel way. Additionally, ...
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Please tell me about "Action at a distance" in Electrodynamics [closed]
I am confused about how test charge informed about source charge. So I research on it. Web said me that it is "Action at a distance phenomenon". What is this? I am a first year Undergraduate ...
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Longest distance travelled by an electron in E&M field
Let's assume we have a cylindrical wire where the currents are following. Since this is not a static case, we would have magnetic and electric field both from the current carrying wire.
Here I have ...
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What effect do two perpendicular magnetic fields have?
What is the effect of 2 perpendicular magnetic fields?
My teacher discussed this illustration in class where there were 2 perpendicular magnetic fields. He said that they both cancel each other out. I ...
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Ampere's law - 2 current carrying wires
I was working on Ampere law questions and starting thinking.
If the attractive force of two parallel current carrying wires was strong enough, could the two wires actually touch? Or do they need to be ...
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Relationship between direction of magnetic force and movement of a ring
Suppose a metallic ring is dropped from above a magnet (N is pointing up and S is pointing down). Why does the "direction" of the magnetic force on the ring stay the same when it enters the ring and ...
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How is a steady current maintained in case of motional EMF if net force on electrons is zero?
I looked at the derivation of emf induced in case of a conducting rod entering a uniform magnetic field perpendicular to it, emf$=Bvl$ if $B$ is the strength of magnetic field, $v$ and $l$ are ...
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force on circular loop due to current in long wire [closed]
my first try is take element at a distance theta from R2 then write force equation and then integrate between -90 to +90 and similarly. but it is getting more complicated. anyone solve this question
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Expression for change in orbital magnetic dipole moment
So, the question I attempted to answer from a physics textbook runs something like this:
"An electron is moving in a circle with radius $r$ and it has a mass of $m$. An external uniform magnetic ...
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Repulsive force from charge accumulation in a capacitor plate?
During a charged state of a capacitor (Regardless of the type of capacitor),
Simple parallel plate:
.png
Parallel plate with dielectric material in the gap:
]3
Supercapacitor:
How is the ...
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Gauge theory of Electomagnetic Potentials - 2nd order derivatives
A quick introduction: In literature of electromagnetic theory, I saw little to no limitation on the formulating of an arbitrary gauge to the potential functions $(\phi,\vec{A})$. Perhaps it's required ...
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Electric field inside current carrying conductor
Is the electric field inside current carrying conductor changing electric field or it is a constant electric field?
And how this electric field produce magnetic field?
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Current geometry and Ampere's law
Under the right circumstances, Ampere's law $\oint \vec H\cdot d\vec \ell=I_{encl}$ can be used to deduce the field $\vec H$ at a point from the current enclosed by the circuit which produces $\vec H$....
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How to calculate pole strength for this magnet?
I know magnetic mono poles don't exists and a magnetic poles always have equal strength. But what about a magnet which looks like this?
This is picture of magnet whose thickness is constantly ...
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Understanding Symmetries and Invariances in Electrostatic Fields [closed]
I'm currently studying electrostatics and I'm having trouble understanding the concepts of symmetries and invariances of electrostatic fields. I understand the basic definitions of symmetry planes and ...
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What is the relation between the Faraday effect and the Zeeman effect?
The Faraday Effect basically says that certain materials under a magnetic field have different indexes of refraction for right and circular polarized light. Linear light which is a superposition of ...
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Would a gauss rifle based on generated magnetic fields have any kickback?
In the case of currently developing Gauss rifles, in which a slug is pulled down a line of electromagnets, facilitated by a micro-controller to achieve great speed in managing the switching of the ...
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Analog between Electromagnetism and Gravity
Feynman makes an analogy between EM field and gravity field in his Feynman's Lectures on Gravitation. The vector field representing EM potential would couple to the current source(vector) in the ...
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Deriving the Yukawa potential from the field of a screened charge [migrated]
I am trying to derive the Yukawa potential from the electric field of a screened positive point charge, which is
$$
\vec{E}(\vec{r}) = \frac{q}{4\pi\epsilon_0}\frac{e^{-kr}(kr+1)}{r^2}\hat{r}.
$$
The ...
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Directionality of EM Waves in Double Slit Experiment
In the experiment of any wave through the double slit we see and model the interference pattern as shown.
In this depiction that means the wave propagates in/out of the page. ie we are seeing a sin ...
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How will change in magnetic field direction affect particle motion?
In a constant magnetic field throughout space, a charged particle undergoes circular or helical motion. But if the field curves as shown, WHY will the particle 'follow' the field?
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