Questions tagged [charge]
A fundamental property of matter which causes it to experience electromagnetic forces.
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How exactly do charged capacitors decrease current?
I recently learned about how capacitors function in electric circuits, and I came across an apparent contradiction that I wanted to ask about. On one hand, I know that as charge builds up on the ...
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Additive term to the lagrangian of accelerated charged particles caused by Larmor radiation in classical mechanics
Considering two interacting charged particles $Q_1$ and $Q_2$, the Euler-Lagrange equations are:
$$\dfrac{d}{dt}\dfrac{\partial L_j} {\partial \dot{q_j}}-\dfrac{\partial L_j} {\partial q_j}=0$$
where: ...
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Could there be multiple fields obeying the same symmetry?
For example, according to the gauge theory a massless, spin 1, Abelian field must be electromagnetic field, but could there be another field which obeys the very same Maxwell’s equation, except that ...
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Why is the electrical field outside spherical (shell) conductor radial if the charge $q$ inside is not concentric with the shell?
Suppose we have a spherical shell that is a conductor and randomly inside the shell a charge $q$. Then inside the shell the electrical field should be $0$. Why is that?
I'm thinking that the ...
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Charge as an intrinsic property of matter [duplicate]
Is charge an intrinsic property of matter? For example, I can induce a static charge and also we see ions which are charged. But from a fundamental aspect, is it an intrinsic property of a substance?
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Griffith, Electrodynamics, 4th Edition, Example 4.8. (Second part)
P.s. This post is a continuation from Griffith, Electrodynamics, 4th Edition, Example 4.8. (First part). I am reading the Griffith, Electrodynamics book, 4th edition, Example 4.8. I want to understand ...
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Time derivative of electric field associated with moving charge
The electric field intensity at a given point in a lab frame will vary in time if the point's position relative to a charge varies in time. If the position of the point from the charge's reference ...
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Feynman's approximation of electric field far away from a moving charge
Feynman in his lectures, Vol 1, chapter 28 gives formula for electric field at point $P$ which is generated by a moving charge $q$ as
$$E = \frac{-q}{4\pi\epsilon_0}[\frac{e_{r'}}{r'^2}+\frac{r'}{c}\...
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How we assigned a charge to everything after defining the charge of electron?
One ampere corresponds to the flow of approximately $6.241 509 074 × 10^{18}$ elementary charges passing a cross-sectional area in one second as per the 2019 revision of SI, fixing the elementary ...
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Explain: Acceleration of charge radiates energy while constant velocity does not. Or does it?
Feynman develops the so-called Feynman-Heaviside formula, similar to the Jefimenko equation
$$\mathbf{E} = \frac{-q}{4\pi \varepsilon_0} \left[ \frac{\mathbf{e}_{r'}}{r'^2} + \frac{r'}{c} \frac{d}{dt}...
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If the field is directed from lower potential to higher then the direction of electric field [closed]
If the field is directed from lower potential to higher then the direction of electric field is taken to be positive or negative there is a lot of confusion, the famous unacademic site on google ...
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What happens to the charges in metals?
Recently in my Advanced Optics class my instructor taught us that in metals the free charge density decays exponentially with time. The exact mathematical expression as derived was
$$ \rho _t = \rho_o ...
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How does charging by rubbing/friction occur? [duplicate]
Electrostatics
Knowledge of insulators and work function
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How do electrons "jiggle" in relation to electromagnetic fields and thermal motion?
When we talk about electrons as sources of electric/magnetic fields, their positions and motions determine the field configurations. At the same ...
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Surface Charge Density of Sphere in Uniform electrostatic field
Let’s say we have a sphere (completely conducting) of radius R and it is now kept in uniform electrostatic field E.
What will be the surface charge density σ in terms of E, polar angle θ, and ...
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