All Questions
Tagged with electromagnetism homework-and-exercises
1,551
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What are the operators here and how are these formulas derived? [closed]
In (23), are grad and div some kind of scalar operators comparing to $\nabla$ and $\nabla\times$? because tbh I dont know how $\text{curl}(\mu^{-1}\text{curl}\textbf{A})$ turns into $\text{div}\mu^{-1}...
- 103
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Electric field in coaxial materials [closed]
Suppose we have two coaxial dielectric materials with $\epsilon_{r1}=2$ and $\epsilon_{r2}=3$ respectively.
If the electric field in material 1 is given by $\mathbf {E_1}=10x\mathbf {a_x}-5y\mathbf {...
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What book should I read to learn about the magnetocaloric effect
I am trying to study the magnetocaloric effect for a project but I can't find any good resources that deeply talk about it.
Could you make any good recommandation to learn the basics about this effect ...
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Magnetic moment of a paramagnetic cylinder
I am currently struggling with a problem where I have to calculate the magnetic moment $M$ of a
cylinder of radius $R$ and height $h$ made up of a paramagnetic material (aluminium) and under a ...
- 13
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Vector potential of Weird loop
I have to calculate the vectorpotential of a current flowing through the loop at the origin:
where the current is given by $I(t)=kt$ for some $k>0$.
Given equations
$$\mathbf{A} = \frac{\mu_0}{4\...
- 49
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Why is charge $q$ chosen as the variable of integration when converting from summation to integral form in electric field calculations?
If we have several point charges $q_1, q_2, q_3, \cdots$, and their distances from a test charge $Q$ are respectively ${\imath}_1, {\imath}_2, {\imath}_3$, $\cdots$, then the electric field intensity ...
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31
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Current sensitivity in transformer scheme with SQUID
I've tried to determine the maximum current sensitivity in this transformer scheme but I'm not sure if my solution is valid. I need to find the relation between the current in the input transformer ...
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How to derive $\partial^{\nu}F^{\mu\alpha} + \partial^{\alpha}F^{\nu\mu} + \partial^{\mu}F^{\alpha\nu}=0$ for the Electromagnetic field tensor? [closed]
The problem says to show that
$$\partial_{[\mu}F_{\alpha\nu]}=F^{\mu\alpha, \nu} + F^{\nu\mu,\alpha} + F^{\alpha\nu,\mu}=0$$ stems from Maxwell equations.
I haven't been able to find this anywhere on ...
- 21
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Where am I going wrong when obtaining the Hamiltonian density for the electromagnetic field?
I'm trying to verify that the Hamiltonian density for the classical electromagnetic field is equal to the energy density. But the electric field is disappearing and only the energy density of the ...
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Question about Fourier-coefficients in Griffith's Problem 3.15 (Electrodynamics) [closed]
I am having some trouble with problem 3.15 from Griffith's Electrodynamics. It states the following:
A rectangular pipe, running parallel to the $z$-axis (from $-\infty$ to $+\infty$), has three ...
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General Form of the Biot-Savart Law for anywhere on the $x$-Axis [closed]
This question is beyond me, and I have very little direction for solving it. I understand that the component of $\ B $ perpendicular to the $x$-axis is 0, and that the component parallel along the $x$-...
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Need help identifying missing boundary condition in charge transport problem
The system I am considering consists of a conducting liquid sandwiched between two electrodes.
The electrodes supply a constant flux of electrons $J_{ext}$.
In the liquid there are also uncharged ...
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Charged pendulum and a fixed point charge
!My set-up is the following: i have an iron bolt suspended on a string next to an electromagnet, of which I steadily increase the voltage and thereby the magnetic field. Supposing the force is linear ...
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Perturbation of central field potential
i`d like to consider system with Coulomb potential: $U = -\frac{\alpha}{r}$ and constant magnetic field.It is easy to write Lagrangian function:
$$ L = \frac{m}{2}(\dot{\rho}^2 + \rho^2\dot{\phi}^2) + ...
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Equations of motion for Lagrangian of scalar QED [closed]
I really would appreciate your help with this exercise.
I have the Lagrangian for scalar electrodynamics given by:
$$\mathcal{L}=-\frac{1}{4}F_{\mu\nu}(x)F^{\mu\nu}(x)+(D_\mu\varphi(x))^*(D^\mu\varphi(...
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