All Questions
31
questions
0
votes
2
answers
49
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Validating Basic Laws of Magnetostatics [closed]
I am having trouble with the following problem, although with similar problems I run into the same issue when it comes to validation. The example problem below is a problem for Amperes Law.
The ...
0
votes
1
answer
591
views
Vector potential of a square loop [closed]
I am doing my homework and I'm really stuck on this problem. It asks for the magnetic field due to a square, lying in the $xy$-plane, of side lenght $a$ and with a electric current $I$ running ...
- 154
3
votes
1
answer
2k
views
Magnetic field due to a finite-length straight wire carrying a constant current [closed]
My question: I want to find an expression at any point in space for the magnetic field $\mathbf B$ produced by a straight wire of finite length $L$ carrying a constant current $I$.
I think that we can ...
- 344
1
vote
1
answer
302
views
Magnetic field in two conducting parallel plates. (stripline) [closed]
Studying Poynting Vector power density I found a geometry that I really can't figure it out and is nowhere to be found on the internet.
I have two conducting parallel plates with opposite surface ...
1
vote
1
answer
37
views
A confusing problem in electro- and/or magnetostatics: two parallel cylinders with opposite currents
I got the following problem as a part of my assignment in physics:
Equal but opposite currents $J$ flow on the surfaces of two cylinders of radii $R_1$ and $R_2$, respectively, with the axes of the ...
- 43
2
votes
1
answer
875
views
Why should there be an induced electric field if magnetic field is constant? [closed]
Problem statement:
The curved surface of a very long hollow non conducting cylinder of radius $R$ is uniformly charged with surface charge density $\sigma$. A non conducting small circular ring of ...
- 362
1
vote
2
answers
328
views
How to find magnetic field as a function of $r$ from axis of solenoid?
I was solving this problem:
Whose answer is given as:
I understand the part for calculating the field outside the cylinder, but for inside, I don't get it. If we apply Ampère's circuital law by ...
- 362
0
votes
1
answer
656
views
Magnetic field of coaxial cylindrical capacitor
I have a coaxial cylindrical capacitor as shown, with inner radius a and outer radius b.
The potential difference across both cylinders is V. I need the magnetic field everywhere when the inner ...
- 21
4
votes
1
answer
1k
views
Current density $\mathbf{J}$ of particle with magnetic dipole moment $\mathbf{m}$ [closed]
I'm solving some excercises on magnetostatics, and encounterded this on which i'm having some trouble. Given a particle of magnetic dipole moment $\mathbf{m}$, show that its current density is given ...
- 97
-1
votes
1
answer
878
views
Cylindrical shell in magnetic field [closed]
Exercise: 'Infinitely long cylindrical shell of inner radius a and outer radius b of material of magnetic susceptibility χ is placed in otherwise uniform magnetic $B_0$ perpendicular to cylinder's ...
1
vote
0
answers
206
views
How to calculate the magnetic field of two cylinders when one of them is rotating
Given is the voltage U and the Angular velocity $\omega$. The rotating cylinder is inside the other cylinder and U is measured between them.
To calculate the magnetic field, I tried to solve
$\oint ...
- 23
0
votes
1
answer
3k
views
Obtaining the magnetic vector potential inside an infinite cylinder carrying a z directed current:
Suppose we have a nonmagnetic conducting cylinder of radius $ \alpha $ directed in the z direction, with a current density $ J_{0} \hat{a_{z}} $. What is the magnetic vector potential for $\rho < \...
1
vote
1
answer
3k
views
Deriving Ampere's law from Biot-Savart equation [closed]
As an exercise, I've been trying to derive Ampere's law from the Biot-Savart equation (in the static case). So basically I'm trying to prove:
\begin{equation}
\nabla \times \vec{B}(\vec{r}) = \mu_0\...
- 71
-2
votes
1
answer
176
views
Consider three infinitely long thin wires [closed]
Each carrying current I in the same direction , are in $x$-$y$ plane. The central wire is along the $y$ axis, while the other along $x=+d$ and $-d$
Find the locus of points for which magnetic field ...
- 41
0
votes
0
answers
42
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Two ways, different result: Find torque due to magnetic force on a conductor
We have an AB conductor of length $2L$ and an infinite one coming out of the screen as shown in the picture (a is the distance between the 2nd conductor and the middle of the finite conductor)
...
- 351