Questions tagged [electric-fields]
For questions that utilize the concept of electric fields (commonly denoted by the letter E), or for questions whose answers likely involve electric fields. More specific than the [electricity] tag, as questions about the phenomenon & theory of electricity do not necessarily involve the discussion of fields.
4,684 questions
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If a large enough electron beam accelerates enough, will its induced electric fields, stop it?
Given acceleration of a beam of charges, there should exist a changing magnetic field around a beam of charges. That changing magnetic field is equal to the negative curl of the induced electric field....
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Can an electric field be induced simply due to the rotation of a conductor about an axis? [closed]
In question such as: this , and this, an uncharged conducting rod rotates about an axis, inducing an electric field, and in turn creates a potential difference across the rod.
I would appreciate it if ...
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Point charge in front of dielectric boundary value problem method of images
Original link to the problem: https://photonics101.com/dielectrics/the-precessing-dipole-molecule.html
According to their setup, I have:
$\phi_2=\frac{1}{4 \pi \epsilon_2}\left(\frac{q}{R_{-}}+\frac{q'...
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Confusion with Wikipedia's derivation of electric field for continuous charge distributions
Here is the page.
My confusion rises from $\textbf{r}'$, exactly from:
$\mathbf{r}'$ is the displacement vector from $\mathbf{r}'$ to $\mathbf{r}$.
Does it mean we're taking $\mathbf{r}'$ as origin?
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Intuitive explanation for the boundary conditions in Maxwell equations [duplicate]
I was looking into the Maxwell equations and was trying to get an intuitive understanding of why there is a difference between the normal and tangential field components. Is there an explanation that ...
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Method of images for an infinite half plane [duplicate]
When applying the method of image charges, is it necessary for the conducting half-plane to be grounded? If the conductor is not grounded, under what conditions can we still justify the use of this ...
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Charge induced inside a spherical conductor with a patch removed [closed]
When solving some problems meant for high school students, I came across this
A thin conducting shell of radius $R$ has surface charge density $\sigma$. A small aperture is made by removing a ...
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What force is the cause for the energy at a capacitor? [closed]
Consider a parallel plate capacitor with capacity $C$.
Let $Q$ denote the charge, while $U$ denotes voltage. Then, $$Q=CU$$
Consider the (approximately) homogeneous Electric Field $E$ between the ...
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How can capacitance exist if a vacuum is used as a dielectric?
As we know, the capacitance is due to arrangement of electric dipoles of the molecules/atoms between the two plates of a capacitor. I read that: if a capacitor (with material medium) is placed in a AC ...
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Connecting one plate of charged capacitor to ground
Lets say I have a parallel plate capacitor of capacitance $C$. I charge it to a potential $V$ using a battery. now I disconnect the battery and the capacitor is supposed to have charges $CV$ and $-CV$ ...
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Heaviside-Feynman formula for electric field vs. Griffiths book formula
I am looking at the Heaviside-Feynman formula for electric field:
$$ \vec{E}(\vec{r},t) = \frac{q}{4 \pi \epsilon_0} \left[ \frac{\vec{e}_{r'}}{r'^2} + \frac{r'}{c} \frac{d}{dt} \left( \frac{\vec{e}_{...
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Intensity of electric field [duplicate]
Intensity of electric field at a point is defined as the force felt by a charge at that point due to the charge creating that field. Why then do we divide the force from Coulomb's law by the charge? ...
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Correct definition of right-circularly polarized and left-circularly polarized
This is a simple question. I am just wondering about the correct definition of left and right circularly-polarized light. I thought that if I point my thumb in the direction of propagation, then in a ...
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Is electric field of point charge invariant under Galilean transformation?
In a physics textbook by Randal D. Knight, there is the following passage:
“Coulomb’s law is still valid in a frame in which the point charge is moving.”
The author say that comparing electric field ...
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Problems with Energy Conservation and Dipole Radiation
The electric field strength of a rotating electric dipole in the far-zone ($d \gg \lambda \gg a$) scales as $1/d$ (Eq 9.18 of Griffiths). Hence, the rate of work done on a second dipole sitting in the ...
