All Questions
Tagged with electromagnetic-induction magnetic-fields
149
questions with no upvoted or accepted answers
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How to calculate the energy transfer between working coil and working piece and dissipated energy of working piece in induction heating?
For who don't know how does induction heating work, a short description can be found here.
However, my question is about physics. Assume I have a coil inductor calculated carefully 50 uH as below:
...
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EMF induced in a loop around a solenoid - Faraday's law
Since the magnetic field outside the solenoid is negligible, it is impossible to detect current in the solenoid from outside.
Suppose I put a conducting loop of large radius, say, $10^9 $ km around ...
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Lighting an Electric Bulb with Earth's Magnetic Field
Yesterday, I was solving some problems of Electromagnetic Induction. Suddenly a thought struck my mind.
Earth has its own magnetic Field.If an aircraft of metallic body is flying in the air then ...
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Faraday's law and a moving charge
Suppose we have a moving point charge with respect to some conductor which has a shape of a closed loop (e.g. a loop of wire). From the conductor's point of view the moving charge has a magnetic field ...
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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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flux threading through superconducting ring
I have been confused over the wording used in this paper describing RSFQ logic circuits: http://www.mukhanov.com/uploads/LikharevSemenov-RSFQReview_IEEETAS91.pdf
From page 6: " If such a single flux ...
- 101
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Induced current created by a magnet falling in a copper tube?
One of the educational demos often shown in schools is to drop a high strength neodymium magnet down a length of copper tube. It takes a considerable time to exit the tube because as it falls it ...
user56903
3
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When a particle changes its spin orientation is it instantaneous?
A change of magnetic field caouses an electric field and an associated potential which is as high as the time derivative of the magnetic field.So is it possible that the change of the spin should be a ...
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Variation of Permeability with DC magnetising Field
For any Powder core, as DC magnetising field increases, the initial permeability decreases known as "permeability roll off".
For example for an MPP core-
For MPP cores the initial ...
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Do the currents of charged particles captured by Earth's magnetic field create their own magnetic fields?
Let me try to illustrate what I mean. Consider e.g. a Solar radiation storm (Solar particle event) where high-energy protons are hurled at Earth from Solar flares. I've tried to illustrate my ...
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How many electrons in a ferromagnetic material, per atom, have their spins pointing in the same direction?
Is there a list or chart somewhere that states, approximately, how many outer electrons per atom in a particular ferromagnetic material are aligned?
Are there, say, five electrons in an FeO2 magnet's ...
- 4,509
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Finding how to calculate the speed of a magnetic train through a coil in a simple DIY Hyperloop model
before I start, let me just say that I am terrible at physics, and this question might have some inaccurate vocabulary. I apologize for that.
I am currently working on a physics model (both ...
2
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1
answer
290
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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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Position of the electric field induced by a magnetic field
I've been told that a cylindrical time-varying magnetic field induces a non-conservative electric field shaped like circles centred at the axis of the cylindrical magnetic field. I suppose it's an ...
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Energy of Magnetic Dipole
What is the total energy of a magnetic dipole, $\textbf{m}$, in the presence of a magnetic field $\textbf{H}_s$?
I've seen the typical answer given is:
$U = - \textbf{m}.\textbf{B}\Delta_v + U_s$
...
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Ocean warming by induced electric current for wandering magnetic poles?
In a post on the co-rotation of Earth and its magnetic field (Does the geomagnetic field rotate?), John Rennie raised the point that, if Earth's magnetic field were rotating about its dipole axis, it ...
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How do you apply "flux-rule" in free space?
Faraday's law of induction states that, the tangential component of the force per unit charge$^*$; EMF produced in a loop of wire, is equal to change in the magnetic flux through the loop,
$$\int_C \...
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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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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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Conductor in motion in a magnetic field
I have the following exercise: there is a square conductor of a given side L and resistance R. The conductor is surrounded by a magnetic field B (90° with the y-axis) and it depends from z: B(z) = K*z,...
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Can magnets induce magnetism stronger then their own magnetism?
This might sound foolish but bear with me for the explanation.
I came across a weird magnetic behaviour playing with coins on a mac. There are magnets in mac, two on the top corners of the screen and ...
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Finding the terminal velocity of a magnet dropped in a solenoid
We have to find proportionality of the terminal velocity with the factors of the system:
Plot: a small dipole(mass $m$) with dipole moment $\mu$ is dropped in a long solenoid (radius $r$, ...
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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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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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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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Is there any way to detect localized magnetic field change in a magnetic material or powdered magnetic material?
Hi I was wondering if there was any way to detect localized magnetic field change within either bulk magnetic material or within like powdered magnetic material. The application we are looking for is ...
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Getting the force somehow using magneticfield force (tesla)
First off, sorry if not everything makes sense, english isn't my first language so some scientific terms may sound weird if they're in English. For a project we are making a coil gun. So we get a ...
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Static toroidal magnetic field rotating inside toroidal winding
what would happen if I took a toroidal core, generated a static toroidal magnetic field in the core and then rotated the core around it's symmetry axis within a larger stationary toroidal winding ...
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Which way does current flow in coronal loops and filaments?
My understanding is this: the Solar surface becomes speckled with more sunspots near Solar maximum, and these spots tend to form groupings known as active regions; each spot is associated with a given ...
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