All Questions
Tagged with magnetic-fields dipole
51
questions
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237
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$H$ field formula
For a permanent bar magnet is there a formula for the magnetic field strength $H$? Just like the electric field strength $E$ can be calculated at a point in space, can we do the same for the magnetic ...
- 425
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78
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Force on a magnetic dipole
How to deduce the force on a magnetic dipole given by $F = \nabla(m \cdot B)$ from the Lorentz force?
0
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1
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Magnetic field around a magnetic dipole and circular current loop
Qualitatively, how does the magnetic field around an ideal dipole compare with the magnetic field around a circular current loop?
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Field of an infinitely wide magnetic dipole
Students commonly wonder about the near-analogies between electricity & magnetism. One such:
The field of an electric dipole in the limit of an infinitely wide plane tends to 0 outside the plane (...
- 970
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Uniform electric field formation in motional emf induction
Why is the electric field $E$ across the ends of a conducting rod, when it's moved with a uniform velocity $v$ in a magnetic field $B$, uniform? Wouldn't it vary non-linearly, since there are opposite ...
- 256
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Magnetic dipole in gradient magnetic field
I know that a magnetic dipole in a uniform magnetic field will precess.
What happens qualitatively (or quantitatively) to a magnetic dipole in a gradient magnetic field? According to Wikipedia, "...
user243050
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2
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553
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Measuring neodymium magnet strength with magnetometer sensor in phone
I try to measure neodymium magnet magnetic field strength, exactly - how it depends on distance to magnet, by using integrated magnetometer sensor in Huawei phone. My setup is like :
Then I move ...
2
votes
1
answer
452
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Is it possible to align a magnetic dipole completely in the direction of field?
considering $L$ is always greater than $L_z$ i.e angle between angular momentum/magnetic moment and magnetic field/z direction cannot be zero. Means $B$ and magnetic moment cannot be in same ...
- 117
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A Classical model for diamagnetism
I'm trying to derive a classical model to describe diamagnetism, and I'd like to understand if it is possible to understand the basic properties of diamagnetic materials with it i.e.:
''A diamagnetic ...
- 307
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2
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534
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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 ...
0
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1
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156
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Can there be a torque-less net force on a dipole in a magnetic field?
I realise that a magnetic dipole moment is essentially defined on the basis of torque, which also seems to imply that a magnetic field imposed on a current-carrying closed loop can only induce a ...
- 256
2
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1
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526
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Why are domains formed as separate units?
I was reading about exchange coupling and domain formation in ferromagnetic materials. As far as I can understand, some of the dipoles in the ferromagnetic material align themselves in a group called ...
- 1,375
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191
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Can we understand a moving charge as a dipole?
I work as a physics teacher at a high school and I have to explain these days the magnetic field of a curreny carrying wire. Of course I may just give the formulae and describe how the field $\vec{B}$ ...
3
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418
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Is the vector potential component $A_\phi$ for a dipole necessarily 0 due to symmetry about the $z$-axis?
Consider an electric dipole (+$q(t)$, -$q(t)$) [where say $q(t)=q_0\cos\omega t$] is placed along the $\hat z$ axis. In the spherical polar coordinates, its vector potential $$\vec{A} = A_r \hat r + ...
user199113
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157
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How to determine the best-fit magnetic dipole Gauss coefficient in a shifted coordinate system?
Introduction
A planetary magnetic field $\vec{B}$ can be described outside of the planet using Gauss coefficients $g_n^m$ and $h_n^m$ and a spherical harmonic expansion:
$$\vec{B} \;=\; -\vec{\...
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