All Questions
45
questions
13
votes
1
answer
560
views
How can I find the position of an image charge when the boundary is parabolic or hyperbolic?
If the position of some charge $Q$ is known, the boundary condition is $u=0$ on some parabolic surface, and we know the image charge has its electric volume of $Q'$, then how can I determine the ...
- 147
9
votes
4
answers
668
views
Distribution of point charges on a line of finite length
How will $N$ freely moving charges confined to a line with length $L$ be distributed? What are their equilibrium positions?
- 4,194
3
votes
2
answers
875
views
Electric field outside wire with stationary current
Consider a conductor of arbitrary structure where a stationary current flow, that is
$$\nabla \cdot \vec{j}=0$$
I did not find on textbook clear explanations on two facts:
How is the electric ...
- 2,617
3
votes
1
answer
1k
views
Electric Field due to a charged sphere
Suppose we have a spherical surface with a surface charge density varying as $cos(\theta)$. Apparently one can find the electric field both outside and inside such a spherical surface by superposing ...
- 33
2
votes
3
answers
206
views
Deriving continuity equation from 4-current of a charged particle
how can i check that following 4-current for a single charged particle
$$j^{\mu}(x)=qc\int d\tau u^{\mu}(\tau)\delta^{4}(x-r(\tau))$$
satisfies continuity equation $$\partial_\mu j^\mu = 0.$$
user391340
2
votes
1
answer
51
views
Arbitrary (Non-Radial) Charge Distribution and Gauss's Law in Integral Form [closed]
Say we have an Electric Field, produced by a charge distribution, given as-
\begin{equation}
\mathbf{E}=c(1-e^{-\alpha r}) \frac{\hat{\mathbf{r}}}{r^2},
\end{equation}
$c$ and $\alpha$ being constants....
2
votes
1
answer
75
views
Two protons inside a negative sphere [closed]
Problem: Imagine a sphere of radius a filled with a negative charge density equal of two electron charge.
Embedded in this is two protons, assume that the negative charge distribution remains uniform
...
- 123
2
votes
0
answers
878
views
Does a rotating disk with uniformly distributed charges have energy radiation? [closed]
Problem:
A disk of radius 10 cm is injected with an amount of charge of 3×10^−12 C, uniformly distributed along the edge of the disk. The disk rotates with an angular velocity of 10 rad/s. Find the ...
- 21
1
vote
2
answers
2k
views
Charged body in hollow conductor : what is the role of insulators and how does the charge distribution change if insulators vs conductors are used?
Question as written in textbook: "Figure 1 illustrates a nested arrangement of four cylindrical conductors (seen side-on in cross-section) in which the cylinders are separated by electrical insulators....
- 1,367
1
vote
2
answers
139
views
Motion of Test Charge in EM Field [closed]
I have a negative infinite sheet of charge moving at a velocity $v$ in the $+x$ direction. A test charge $Q$ with mass $m$ moves at a constant velocity $v$.
My Question is simple: How will the test ...
- 313
1
vote
2
answers
1k
views
Zero electric field in empty region of hollow conductor
A hollow conducting shell having a net charge of +Q has a point charge -Q placed at its centre.
From the diagram, it looks like
Suppose the radius of the inner shell from the origin is a and the ...
- 889
1
vote
2
answers
423
views
Description of the motion of the COM of a system of charged particles moving in a magnetic field
I recently came across a problem where an electrically neutral particle is at rest in a uniform magnetic field. The particle now splits into two charged particles of equal mass $m$; charge and mass ...
- 2,077
1
vote
1
answer
57
views
Determine the charge distribution and the total charge of the system [closed]
Suppose we have a spherical symmetrically distributed charge in vaccuum which yields us a spherically and symmetrical potential $V(r)$ according to:
$$V(r) = V_0(1-(r/a)^2)$$
for $r\leq a$ and $0$ ...
- 344
1
vote
1
answer
337
views
Why can't I measure electric potential from source to point according to this formula
The formula for electric potential of points A and B in the presence of an electric field due to a point charge where $R_a$ and $R_b$ are the distances from source to point A and B respectively is:
$${...
- 163
1
vote
1
answer
48
views
a charged particle path [closed]
A particle of mass $m$ and charge $e$ enters a homogeneous and stationary electric field $E$ with velocity $v_0$ perpendicular to the direction of the field.
Calculate the particle's path?
What does ...
- 145