All Questions
Tagged with electromagnetism homework-and-exercises
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I am trying to derive an expression for the magnetic field of charged particles travelling at significant fractions of speed of light [closed]
I tried using lorentz transformation , which gives me correct answer for speed of light c but when i try to input any other values nearby c it becomes a constant
B = 10-7 . q/r² ( (v - u)/ 1- uv/c²)
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Transformers: How does current in primary coil change?
I was doing a question on transformers and found this really confusing question:
A 100% efficient transformer converts a 240V input voltage to a 12V
output voltage. The output power of the ...
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Direction of Magnetic field caused by straight current-carrying conductor [closed]
The question: Two crisscrossing insulated wires contain currents as displayed. Find the total mag field at points P and Q, assuming the horiz current moves (a) right and (b) left. QUESTION is for part ...
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Force acting on an infinite wire with current inside a magnetic medium
I've recently stumbled on an electromagnetics problem that I don't quite understand.
There is an infinite wire carrying current I that is placed inside a medium with magnetic permittivity μ1. At a ...
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Motion of a magnet inside a solenoid
I have a homework problem where a bar magnet is placed halfway inside a horizontal solenoid. A cut away shows that the magnet's north pole points to the left of the page and the south pole is outside ...
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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}...
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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 ...
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Location of high and low potential points in motional emf
Okay so in the above image the semi circular loop is rotated and a sector of it is introduced into the magnetic field.
Questions:
I know the magnetic field is constant so no non conservative ...
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Finding equation of motion of Lagrangian density: What does the location of the indices mean?
We are given the following Lagrangian density:
$$\mathcal{L}=F_{\mu \nu} A^{\mu} \mathcal{J}^{\nu}$$
where $F_{\mu \nu}$ is the electromagnetic field tensor, $ A^{\mu}$ the 4-vector of the vector ...
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How to find the mixed tensor, contravariant tensor and tensor trace of $F$?
I have a question in particle physics that ask me to find the mixed tensor, contravariant tensor and tensor trace of $F$:
Our professor didn't teach us that much about the math of tensor, which makes ...
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Fall of a square conductor loop perpendicular to a homogenous magnetic field
This is my homework. I am not asking you to complete it for me - I just need a push in the right direction so I can complete the rest. The question is translated from German, so it reads a bit awkward....
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Self-inductance of a finite solenoid
Where did the $l$ in the denominator come from? I am talking about the $l$ in muNI/2l[...]?
I can't match LHS and RHS.
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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 ...
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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\...
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