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Tagged with electromagnetic-induction magnetic-fields
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Currently arguing with my teacher about this electromagnetism question, any helpers?
Sorry if my Q is simple, I'm still in high school.
I'm currently arguing with my physics teacher regarding a Q, shown below.
The answers state this.
However, I am attempting to argue that the ...
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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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Should a wire loop moving through a constant rectangular magnetic field directed perpendicular to it's motion have zero induced current in the middle?
Suppose we have a loop of copper wire moving perpendicularly through a constant finite rectangular magnetic field directed into the screen .
When the loop enters the field, the induced current would ...
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What is the difference between the induction of a magnetic field $B$ and the magnetic field strength $H$?
I just started learning about magnetic fields by myself. In my textbook it says that the magnitude or intensity of induction of a magnetic field is equal to the amount of field lines that pass through ...
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Does the electric field ($E$ caused by induction) of a moving conductor in a magnetic field drop when connected to a curcuit?
We know that when a conductor moves in a homogenous magnetic field that is perpendicular to itself due to the amount of electric charge gathered on one end of the conductor( as a result of the lorentz ...
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Infinite charged sheet kicked into motion - Electric field direction?
In volume two of the Feynman Lectures on Physics, Chapter 18, here: http://www.feynmanlectures.caltech.edu/II_18.html
There is a scenario in which an infinitely extending charged sheet is suddenly ...
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How does magnetic hysteresis (ie. the $B$-$H$ curve) transform the input-output of a guitar pickup or speaker?
I understand that magnetically dependent equipment like a guitar pickup or speaker are affected by magnetic hysteresis.
Here is an article discussing the effect on speakers for example. That article ...
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Induce electric field in an incomplete circular conducting loop
I was solving a numerical example(image1) of 'Griffiths book of electrodynamics'
And in this solution it is given that if there is a changing magnetic field is there there would be induce induce ...
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Internally, what defines whether a material is magnetically hard or soft?
I know that magnetically hard materials hold magnetic fields (magnetic moment alignment) for longer, while soft metals do not. However, what, internally, causes these properties to arise?
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Do transformers return current to source when magnetic field collapse at primary coil?
When we close the circut containing an inductor and a battery, the current starts flowing, which builds magnetic field around inductor, changing magnetic field produces its own current in opposite ...
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Confused between induced emfs
We know when flux of B changes an EMF is induced in loop
And also when a rod moves in mag field Potential difference between its ends is also produced.
So is this ques while writing Potential equation
...
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Mutual inductance - induced magnetic flux in the primary
Let there be two coils, L1 (with self inductance L1), and L2, with self inductance L2.
The first coil is connected to a sinusoidal supply, and the second one is connected to a resistor load, as shown ...
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Torque on a rotating sphere in a uniform magnetic field
Consider a uniform magnetic field. We know that if we have a conductive loop rotating in this magnetic field then we get a current running through that loop due to Faraday's Law, which in turn exerts ...
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Magnetic flux and number of turns
The number of windings is not written in the magnetic flux formulas in high school textbooks, but I come across articles saying that the number of windings affects the magnetic flux formulas. Is this ...
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Magnetic energy terms of system of three circuits
Say we've got a system of coplanar circuits like in the picture with same electric current flowing through them
We know that a system of circuits has magnetic energy
$$\mathcal U_{\,\mathrm m}=\dfrac{...
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Work done in a moving conducting bar and in a Faraday disk
I deeply apologize for my ignorance, but I am asking this since I still can't seem to grasp what my teachers relayed to me a few days ago about two exercises that I solved in an intrinsically wrong ...
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How does any changing magnetic field induce voltage?
Hopefully the title puts in well enough;
a charged particle moving in a magnetic field experiences the Lorentz-Force. If this occurs in a wire and part of the circuit is outside the B-Field then a ...
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The direction of the induced electric field
Recently I got stuck witht the following problem.
Imagine we have uniform a magnetic field which induction points upwards. The fields strength is steadily decreasing. If we put an iron coil ...
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What is the reletive permeability of structual steel?
Help, i need to know what the reletive permeability is of a few materials (listed below) but i can not find the data on the internet. Does annybody know the data or where i can find it?
-s235jr
-...
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How do Relativity explains electromagnetic induction in the case of changing $\bf{B}$ with both loop and magnet at rest?
Here is how Griffiths lists the experimental evidences of electromagnetic induction.
Case 1 can be explained with Lorentz Force. I understood how Special Relativity relates case 2 to case 1, ...
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What is the difference between paramagnetic and ferromagnetic?
What is the difference between paramagnetism and ferromagnetism?
Before answering, I want to note my difference between the rest of the similar questions on this website: from what I think I know, ...
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Emf induction in a conducting coil placed in a variable magnetic field
Consider a conducting coil placed in a variable magnetic field. By the laws of nature, an emf will be induced in the coil. Between which two points is the emf induced in the coil?
If we consider it to ...
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What area should be chosen for finding EMF induced when only magnetic field $B$ is changing?
Suppose i have a region with uniform magnetic field which is changing with time.
For finding EMF induced in a conductor, we use $\frac{d\phi}{dt}$, where $\phi=B.A$ (as $B$ is uniform).
$$\implies EMF ...
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Is the induced electric field generated due to the separation of charges in a moving wire in a magnetic field non-conservative?
As the title suggests, whenever there is a moving wire in a magnetic field of constant magnitude, an induced voltage is produced. Now, due to the separation of charges, which is a result of the ...
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How is the magnetic flux density inside a current tube affected by an inner wire?
Background to problem
Conventional wisdom informs that the magnetic flux density inside a tube carrying current is zero everywhere. Pictorially this is represented by this finite element analysis (...
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Straight wire cutting magnetic flux - Faraday's law
For a straight wire moving perpendicular to a uniform magnetic field in velocity v,
$$ε=\dfrac{\Delta \Phi}{\Delta t}=\dfrac{BLv \Delta t}{\Delta t}$$
So the induced e.m.f in the conductor as it moves ...
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Ring Magnet with a wire in the middle
I have a very specific question concerning a system with a magnet and a wire.
Consider a ring magnet with a magnetic field directed right through its center. In the center of the magnet is a wire, ...
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What happens if I have a square conducting wire being permeated by a magnetic field and the field suddenly disappears?
Suppose there is a square conducting wire in a magnetic field. The two vertical branches will have the same emf, and the two horizontal branches will have 0 emf, resulting in a net emf of zero and ...
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Is this a correct way of finding magnetic field of a magnet created with Wasilewski's method?
$\quad$ Wasilewski's method (Or the method that could be seen in Dr Stone episode 9) consists of piece of iron being struck by a lightning, which then magnetises it. Let's say, we have a cylindrical ...
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How to calculate retarded potential (for magnetic field calculation) for a group of current carrying loops where the magnitude of current is changing?
For constant current, the magnetic field seems to be easy to calculate because of Biot-Savart Law. For a loop having varying magnitude of current (simplifying an electromagnet), however, it seems that ...
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What is the induced electric field in a moving conducting material in a magnetic field?
I've been taught that the induced EMF in a conductor is the rate of change of flux in it, but Maxwell's equation
$$
\nabla\times\vec{E} = -\dfrac{\partial\vec{B}}{\partial t},
$$
only states so for ...
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Flux and emf induced graphs when magnet is dropped through a coil
I've been told that if you drop a magnet through a coil the induced emf and flux graphs would look like this:
I understand that when the bar magnet is in the middle of the coil the emf induced is ...
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Does making a magnet move require more energy than a non-magnet?
I know that electric fields store energy, with their energy in an infinetesimal volume being proportional to $E^2$ at that point. I also know that a moving magnet creates an electric field (...
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Electric field of moving charge
Does the electric field of a moving charge (constant velocity) change with time? Or it remains the same?
I know that changing electric fields produce a magnetic field, but in a straight, current-...
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Explaining how a magnetic field affects currents in a conductor, in the limit of high conductance
Recently, I gave an answer to this question,
explaining my intuition on how much electric field impinges into
a good conductor under certain conditions, in order to reason about the limit of
perfect ...
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Self-induction in a permanent magnet
when a permanent magnet is moved in a coil, an emf is induced in the coil. so is an emf also induced in the magnet itself? and if not then why not. and if I replace this permanent magnet with a ...
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Finding induced magnetic field strength given current.
I'm working on a project involving a Tesla Coil, and I was hoping to figure out how strong an induced magnetic field would be with an input voltage of X. Is there an equation to help solve this? I'm ...
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Why does a changing magnetic field produce a current?
A changing magnetic field induces a current in a conductor. For example, if we move a bar magnet near a conductor loop, a current gets induced in it.
Faraday's law states that
The E.M.F. $\...
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What logic is being used in Bleaney & Bleaney to prove the reciprocity theorem for mutual inductance?
I'm currently reading Bleaney & Bleaney 3rd Ed. On pg 136 they discuss the case of 2 coils. Their logic is as follows:
If a second coil is brought near to a coil carrying a current $I_1$, there ...
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Induced current density and magnetic field arising from forced oscillations of particles in a constant magnetic field?
I am being confused by what should be a simple physical scenario. Let's say I have a small, cylindrical region of radius and height are both $a$ filled with a medium of both positive and negative ...
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Faraday's law and motional EMF
My understanding of motional EMF is that one of the ways it is created is by moving a conductor (moving such that its orientation doesn't change) in a uniform magnetic field (non changing). EMF is ...
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How do Electric and magnetic fields generate each other (mathematically)?
Regarding electromagnetism, a changing magnetic flux$(\phi_B)$ produces emf by-$$EMF= -\frac{d \phi_B}{dt}\tag1$$
This emf creates a current which again creates a magnetic field given by-(bio-savart ...
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What factors does magnetic field due to a circular loop depend on?
I know of three.
Strength of current
number of loops ( a cheeky way to 'increase' current?)
radius
I'm having doubts about radius of circular loop affecting the magnitude of magnetic field ta ...
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Induced Electric field due to magnetic field in Faraday experiment
Regarding this experiment where a magnet is moved in and out of a coil -(see the picture)
what i considered to be true is that when there is a changing magnetic flux through the coil(due to changing ...
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Cause of induced EMF in a loop
Len'z law states that the change of magnetic field in a loop of wire produced current in a wire as the magnetic field in and out the loop.Although it just true experimentally, but
i) What happened ...
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Are there losses in an ideal transformer?
In a circuit with an AV power source $V$ and a zero-resistance ideal coil, the power from the source. $P_{in} = IV$ is equal to the rate of change in the magnetic energy $U_B$ stored in the coil. The ...
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How is the direction of current induced by the induced magnetic field determined in a metal detector?
In the figure below, from a textbook explaining Eddy Currents, a pulse of current is sent and generates a magnetic field $ B_0 $. The magnetic field produces a change in flux in the metal box that ...
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I can’t figure out the magnetic field around a non-straight wire
Say I have a circuit where the wire has a shape defined by some closed
Parametric defined as $(X(t), Y(t), Z(t))$ (it is a loop), how do I calculate the entire magnetic field around the circuit?
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Magnetization current when two magnets are brought together and the Lorentz force law
Suppose we have two ferromagnetic objects constituting two permanent magnets. A classical way to think of the two magnets repelling/attracting each other would be by ascribing bulk and surface ...
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