All Questions
Tagged with voltage electrostatics
477
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Electrostatic potential outside of a charged ball [closed]
To preface, I have never solved Maxwell's equation or his resulting Poisson's equation in any coordinate scheme, nor am I a physics major. I'm entirely teaching myself how to do this, so I don't know ...
- 121
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Does the geometric shape of the cross-section of an infinitesimally thin conducting charged thread (wire) affect its electric field?
Assume that a solid conducting torus (toroidal ring), with a cross-section of a circle of (minor) radius $r$, is negatively charged. Solving Poisson's equation, we can find the charge distribution of ...
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Voltage: work to move a charge, or difference of electric potential?
Let's say I have a single positive charge inside of an electrostatic field. I want to move this charge from point A to point B and determine the voltage between the two points.
Points A and B are the ...
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Maxwell stress tensor on a capacitor late given a dielectric
Given a capacitor with large plates (area $A$) separated by a dielectric with relative permittivity $\varepsilon_r$ and thickness $g$, I believe the Maxwell stress tensor states that the force on each ...
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How do I compute the voltage accross a cell membrane given microstate of neuron (distribution of charged ions)?
I am not a physicist, and I'm not sure what keywords to use to search for this.
I'm trying to understand how I could in theory quantitatively know, what the voltage across a cell membrane in a Neuron ...
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Why is the electric potential from a positive sphere not negative? [duplicate]
Say we have a positive point charge located somewhere. Then the electric field due to this point charge is
$\vec{E} = \frac{1}{4\pi \epsilon_0}\frac{Q}{r^2}\hat{r} $ , now considering potential is $V =...
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Does cutting out the surfaces with no surface charge affect the charge distribution on the remaining parts of a conducting surface of arbitrary shape?
Assume that we have an arbitrary conducting surface being charged positively/negatively. Also, assume that we have extracted charge distribution by solving the Poisson's equation with proper boundary ...
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Series Solution of Laplace Equation in Spherical Coordinates
I was recently Studying Griffiths Electrodynamics after a long time and there I saw the Laplace equation. Because it was my second time going over Griffiths so I thought maybe I should try to derive ...
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Capacitors with same capacitance but different voltage ratings
Suppose we have two capacitors that have same capacitance (same dielectric material) but different voltage ratings. Let both capacitors each be fully charged to their maximum voltages. From formula $Q=...
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Can a positive charge have a negative potential?
I'm studying about electrostatic potential due to a point charge and was wondering - can a positively charged point have negative electrostatic potential?
V=Kq/r for a positive point charge.
Assume B ...
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Confusion about reference point for potential difference
My confusion comes from trying to find the potential difference of a spherical conductor with an inner shell of radius $R_1$ and an outer radius $R_2$.
I tried using a reference point of $R_1$ and ...
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Equipotential surfaces
Why two equipotential surfaces cannot intersect What is the logic and reason behind it?I know that two electric field lines cannot intersect but what about equipotential surfaces?
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Electrostatics: Electric Potential of Earth [duplicate]
I have a very basic question which is: Why we consider the potential of Earth to be zero?
Generally in physics we consider the electric potential at infinity to be zero. But while reading about ...
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What does this formula of Electric potential generated by spherical symmetric charge density mean?
I found this formula (14.5) in the book Classical Electromagnetism in a Nutshell by Anupam Garg,
$$\phi(r) = \frac{1}{r} \int_0^r 4\pi r^2\rho(r)\;dr+\int_r^{\infty}4 \pi r\rho(r)\;dr.$$
I know it's ...
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Equation of a equipotential surface
I have been trying to find a equation for the equipotential surface of a dipole , so I started with a simpler system of a singular charged particle , here are few things I know about the equipotential ...
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