All Questions
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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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1
answer
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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 $x$-...
- 3
1
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EMF generation by rotating rod without magnetic field [closed]
what is the EMF generated by a conducting rotating rod of mass $m$ and length $l$ in free space without magnetic field. the rod is roating with angular speed $w$? also find the current if the rod has ...
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Non-standard circuit
I partially solved this problem.
Problem: A charged sphere of radius $a$ is connected through a resistance $R$ to the earth. An electronic flow breaks out towards the sphere of infinity at speed $v$ ...
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1
answer
49
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Why can the current in this region be represented as this formula?$I_{in}=I-I\frac{r^2-b^2}{c^2-b^2}$ [closed]
An air coaxial transmission line has a solid inner conductor of radius a and an outer conductor of inner radius b and outer radius c. Find $\vec B$ as a functions of radial distance r.
The region in $...
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Where does force act in two parallel current carrying conductors?
F=ILB.so consider length as 5 m and I as 2 ampere and B as 5 T.so the force is 50 N.does this 50 N act at one point or equally applied on full length like pressure.So what does force/length in this ...
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146
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What is the expression for current density of a ring in spherical coordinates [closed]
I am not understanding the following expression for the current density of a ring of radius $a$ : $$J_{\phi}= I \sin\theta'\delta (\cos\theta')\delta(r'-a)/a.$$ It is dimensionally correct. I do not ...
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How to derive the magnetic field at a point a distance $x$ from the center of the axis of a circular loop of radius $R$ carrying current $I$? [closed]
Question: What is the magnetic field at a point a distance $x$ from the center of the axis of a circular loop of radius $R$ carrying current $I$?
I was given the answer $\frac{\mu_0}2 \frac{IR^2}{(x^...
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1
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Drift velocity current electricity [closed]
I have a question which I got stumbled upon between two different options (MCQ), as it required to have only one correct option. So the question goes like this:
In a metallic conductor, under the ...
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282
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What's wrong in the concept/method I applied for the below electromagnetism problem?
I was told by mathstack community to post it here.
The setup was this (figure added): a semi infinite wire straight current $I$ being given to a plane sheet (current flows radially there).
Find ...
- 117
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2
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679
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Application of Biot-Savart's law on a current-carrying wire of finite length
In this figure, how will the wire elements between O&a and O&-a affect the magnetic field at point 'P' which lies at a distance x from point O? Because none of the field lines created due to ...
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1
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106
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How to find current density given resistor, and voltage, using Ohm's law in this case?
I was wondering about how to find current density, given a resistor and an electromotive force.
resistor's data are: resistivity = $\rho$, length = $l$, and cross sectional area = $A$.
resistor = $\...
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2
answers
293
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How is current produced by one rotating charged sphere? [closed]
I was doing this problem today:
This question came in the Dhaka University admission exam 20-21
Q) A sphere with charge $q$ is rotating by a non-conducting string at an angular speed $\omega$. What is ...
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How does the actual power of the device depend on the angular frequency of the voltage? [closed]
The voltage source produces a sinusoidal AC voltage. An electrical device with resistance and inductance is connected to the source. How does the actual power of the device depend on the angular ...
user331916
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Continuity of magnetic field - infinite wire [duplicate]
Our system is an infinite wire with cylindrical symmetry and radius R, the wire is made of copper.
The current density is given by:
$\frac{p}{R} \hat{z}$, p<R
0, p>R
What is the magnetic field ...
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