All Questions
Tagged with magnetic-fields dipole
51
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4
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734
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Formula for force on a magnetic dipole
Using the magnetic current model, the force on a magnetic dipole, commonly derived in textbooks, is found to be:
$$
\mathbf{F} = \nabla(\mathbf{m} \cdot \mathbf{B}) \tag{1}
$$
If the magnetic pole (&...
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0
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Linear approximation of the magnetic dipole field
Summary: using 3 angles to represent a magnetic dipole's orientation is redundant because the rotation around the $z$-axis of the dipole does not change the magnetic field, there are only 2 DOFs for ...
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0
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Orientation of Magnetic Induction of a Dipole Source in MEG
I am working with source-reconstructed MEG data, and what I would like to know is that
when we obtain the magnetic induction (using the right-hand thumb rule) of a dipole source, is it only the ...
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0
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Equation relating the current carried by a solenoid to the force experienced by a magnetic dipole?
I am trying to find an equation or a series of equations that relates the current I carried by a solenoid of length L with turns N to the force F experienced by a magnetic dipole of strength M that ...
0
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1
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Knowing the force of attraction of two bar magnets what is the force between two surfaces made of the same material?
Two bar magnets with area $a$, in axis, at a distance of $d$ ($d$ is much biffer than $a$) attract each other with a force of $F$.
What is the force between two infinite surfaces made of the same ...
CommunityBot
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2
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Source of magnetic dipole potential energy
One of the basic expression that goes without much thinking is the potential energy expression of a magnetic dipole in a magnetic field, $$ U = -\mu\cdot B $$
In the case of electric and gravitational ...
CommunityBot
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2
votes
1
answer
494
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The force on a magnetic dipole in a non-uniform magnetic field
Let's say there is a non-uniform magnetic field $B=(0,0,z)$ (i.e. the field is parallel to $z$-axis and the amplitude is linearly changing along $z$-axis). If there is a current loop (=magnetic dipole)...
- 49.9k
1
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1
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Classical dipole-dipole interaction in iron
I've been reading about the classical magnetic dipole-dipole interaction and I'm wondering how it would work in a ferromagnet element like iron (theoretically under the assumptions I will write below)....
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How to determine the best-fit magnetic dipole Gauss coefficient in a shifted coordinate system?
Introduction
A planetary magnetic field $\vec{B}$ can be described outside of the planet using Gauss coefficients $g_n^m$ and $h_n^m$ and a spherical harmonic expansion:
$$\vec{B} \;=\; -\vec{\...
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How can the magnetic field of a dipole be exceedingly large close to its singularity?
I am trying to figure out the magnetic field close to a micrometer sized bar magnet in my experiment. The field gets detected 1 micrometer away from the north of the bar magnet. For now, I just take ...
- 207k
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Earth magnetic field, WMM/IGRF
I am studying about World Magnetic Model (WMM) and International Geomagnetic Reference Field (IGRF) models. It is well known that, to a first approximation, earth magnetic field is a field of dipole. ...
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3
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Isn't magnetism governed by the inverse square law? [duplicate]
Why does magnetism appear to decay much faster than gravity with distance?
A clear indication of this is the fact that a magnet that in short distance able to overcome gravity and pick up some object,...
- 95.5k
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Non-parallel magnetic dipole falling throug copper tube
What happens with magnetic dipole while falling through copper cylinder?
If it's parallel to z-axis (shown on picture below with red color) we know that it stays parallel to the z-axis all the way ...
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1
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Force components on dipole falling through copper ring
We have a magentic dipole parallel with z-axis (shown on the diagram below) falling through copper loop, because of changing magnetic flux there is induced current in cooper ring/loop and consequently ...
- 49.9k
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2
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Does the force between two magnetic poles ever reach zero?
If we hold two magnetic like-poles together and start to move them away, would the repelling force reach absolute zero at certain point?
In that scenario, as a layman, I think that there is something ...
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