Questions tagged [electromagnetic-induction]
This tag is for questions regarding to electromagnetic induction, a process in which a conductor is put in a particular position and magnetic field keeps varying or magnetic field is stationary and a conductor is moving. Electromagnetic Induction was first discovered way back in the 1830’s by Michael Faraday.
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How to find permeability of a magnetic material?
I have been working with magnetic materials for quite some time now and never really explored this fundamental parameter. After looking through the literature I realize there and quite few different ...
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Ampere's law on solenoid, using a circular loop
Suppose we take a long and tightly wound solenoid with current I going in it. We can find the field inside, by ampere's law, taking a rectangular loop and assuming the magnetic field just outside the ...
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What happens to the charges in an inductor when you induce a voltage?
Say you have two inductors, and - very much like a transformer - you connect the first one to a voltage source, then place the other one close to it, so that there will be an emf induced by the change ...
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Can plasmas have eddy currents?
A couple days ago I asked a question on if plasma could have a magnetic field due to current which was a yes. Now I am wondering again on if plasma can possess eddy currents. Assuming a time varying ...
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How is a steady current maintained in case of motional EMF if net force on electrons is zero?
I looked at the derivation of emf induced in case of a conducting rod entering a uniform magnetic field perpendicular to it, emf$=Bvl$ if $B$ is the strength of magnetic field, $v$ and $l$ are ...
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How does the induced current flow? From positive to negative or the opposite?
Let's say there's a rod and it in moving horizontally in a magnetic field (changing flux so current is induced). Using Fleming's right hand rule, we find that induced current flows from left to right. ...
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Terminal velocity of a bar magnet in a long conducting tube (quantitative)
If a bar magnet is dropped into a copper (conducting) tube, it reaches a terminal velocity. I'm trying to derive this terminal velocity.
We know from Lenz's law that $e=\frac{-d\phi}{dt}$.
I'm facing ...
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Isn't the induced electric field vector always tangent to the loop?
In the law of electromagnetic induction: $$\mathcal E_\text{ind}\equiv \oint_\Gamma \mathbf{E_\text{ }}d\mathbf l = -\dot \Phi_\mathbf{B}(t)$$
Here, $d\mathbf l = \hat{\mathbf t}dl$ is taken along the ...
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Straight wire in moving uniform magnetic field induced emf
My question is a follow-up to this one.
The green dotted line is the arbitrary loop which is constructed in the calculation of emf in the wire of length L. x is a variable which can be changed to ...
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Can a satellite generate electricity by using a planet's magnetic field? [duplicate]
I am entering AP Physics E&M and don't have much knowledge about electricity but always had an idea based on my limited knowledge.
If a satellite had a metal coil inside of it, wouldn't it have an ...
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Faraday's and Kirchoff's in RL circuits
I know this question has probably been asked a 100 times over on this site and there is a whole controversy on it but I still don't understand the explanations and had to ask it again. First of all I ...
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Growth of Current in an Inductor Connected Across a Battery [duplicate]
When baterry is connected across inductor with no resistance in circuit, won't the current flowing through it be zero, as inductor back emf will counteract the effect of potential difference due to ...
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Cannot catch a minus sign mistake when deriving the ODE for an LC circuit
It's probably a very basic question but I just cannot wrap my mind around it. I'll just try to derive the differential equation for an LC circuit:
According to the law of induction, in a solenoid we ...
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Effect of catapult field on the weight of magnets
Diagram shows a metal rod, PQ placed perpendicularly to two permanent magnets and connected to an electric circuit. The steel core containing the two magnets is placed on an electronic balance. What ...
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Why is induced EMF in DC motor being included in Kirchoff's Loop Rule
I was reading some lecture notes (don't think I can include them here) that show the EMF induced in the armature of a DC motor, being included in the equation of Kirchoff's Voltage Law for the ...
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