All Questions
Tagged with terminology electrostatics
35
questions
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Can the potential of a point charge be considered one-dimensional?
It is well known that,take infinity as 0 potential,the potential at position r of a point charge q placed at the origin is
$$V = \frac{1}{4\pi \epsilon _0}\frac{q}{r}$$
it satisfies three dimensional ...
- 109
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1
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89
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Dirichlet’s Theorem and Solutions to Laplace Equation in Cartesian Coordinates
I have been reading Introduction to Electrodynamics - Griffiths about solving Laplace equation in cartesian coordinates, and in that book, I saw this statement:
The functions $\sin(n\pi y/a)$ are ...
- 97
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1
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36
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Dielectrics terminology
I got confused while reading about dielectrics, so basically my question is:
(a) what's the difference between a (homogenous and isotropic) dielectric and (linear) dielectric? Does the first imply the ...
- 294
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What is the proper term for the linear, surface area, and volume components in density equations?
Say one is looking at charge density. Linear charge density would be given by
$$
\lambda = \frac Q \ell
$$
surface charge density would by given by
$$
\sigma = \frac Q A
$$
and volume charge density ...
- 329
3
votes
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Difference between streamlines of $\vec{E}$ electric field E and electric field lines of $\vec{E}$?
I don't understand how streamlines are related to electric fields. I thought they are related to the lines of fluids.
I searched and saw that streamlines represent curves of velocity vectors, whereas ...
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Meaning of reference radius in multipole expansion
I have a given electrostatic potential $\Phi(x,y)$ in 2D and want to see how different it is from a some multipole potential (eg. quadropole).
The expansion in the multipole terms is
$\Phi(x,y)= \...
- 195
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55
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What is the difference between electrostatic and electric potential energy? [duplicate]
In circuits what is the difference between electrostatic and electric potential energy?
Side question does electrostatic potential energy even exist in a circuit?
user337772
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Terminology: does this situation correspond to an anisotropic but linear dielectric?
Let us assume that for a dielectric the relation $${\vec D}=\epsilon\vec E$$ holds where $\epsilon$ is independent of $\vec E$. However, let $\epsilon$ is not a scalar number but a tensor (or a $3\...
- 11.7k
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4
answers
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Are capacity and capacitance the same?
Consider two parallel plate capacitors, one with a separation between plates of $d_1$ and other with $d_2$, where $d_1,d_2\ll\sqrt A$, and where $A$ is the area between the plates and both in the same ...
- 882
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What does 'per unit charge' mean?
When we say "potential is the potential energy per unit charge", what does a 'unit charge' actually mean?
In a worked example from my textbook, when they find the potential difference, they ...
- 372
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3
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Difference between electric field and electric force
What is the difference between electric field and electric force? Both seem to do the same thing, but their formulas are different.
- 11
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Why is $\vec{D}$ called displacement field and not $\vec{E}$?
I'm repeating my electrodynamics knowledge and immediately had a very easy question which drives me crazy (and not a dupe, at least I didn't find a suitable answer, although many similar questions):
...
- 1,803
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What do we mean by electrostatics when charges are in motion?
Charges are always in motion, so what exactly does electrostatics refers to, is it a hypothetical concept or does it hold any sense in particle quantum physics?
- 3
14
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6
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Is there a name for what Feynman called a fundamental constant i.e. "ratio of electrical repulsion to gravitational attraction between electrons"?
Paraphrasing from Feynman's lecture on physics, from the chapter on gravity
If we take, in some natural units, the repulsion of two electrons (nature’s universal charge) due to electricity, and the ...
- 4,476
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Why is the cathode filament in an x-ray tube negatively charged?
Quoted from BU-104b: Battery Building Blocks:
The electrode of a battery that releases electrons during discharge is
called anode; the electrode that absorbs the electrons is the cathode.
Based on ...
- 797