All Questions
Tagged with magnetic-fields dipole
51
questions
2
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Can I replace a multipole expansion by a combination of separate dipoles?
If I want to be able to model a magnetic field flux density $\mathbf{B}$ from a magnetic source located at the origin at a position $\mathbf{r}$, it is my understanding that I can represent $\mathbf{B}...
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-1
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3
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5k
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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,...
- 153
3
votes
1
answer
780
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Point particle with a magnetic dipole?
I have read these questions:
Are contravariant basis vectors and basis 1-forms identical?
Where John Rennie's answer says that electrons do have an electric dipole moment and we imagine that in math ...
- 29k
0
votes
2
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152
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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 ...
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1
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80
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Function of dipoles in particle accelerators
I know now that quadrupoles are used to focus the beam in a particle accelerator, but what about dipoles? Are they used to center or accelerate the beam?
The number for the LHC magnets I think it is ...
- 910
3
votes
1
answer
3k
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How do I graph a magnetic field?
For a school project, I'm trying to graph a magnetic field. I found this page on the NASA website with spherical coordinate equations for a dipole field, but I'm having trouble interpreting the page.
...
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3
votes
3
answers
6k
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Determining North and South pole of magnet
If I have an irregularly shaped magnetic material and want to find which way is the north and south. How do I do it?
And more importantly, why are the north and south poles of a magnet situated where ...
- 478
15
votes
3
answers
2k
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Electromagnetic field energy "paradox"
The starting point is the energy density in electromagnetic fields:
$$ u = \frac{1}{2} \left( \epsilon_0 |\mathbf{E}|^2 + \frac{1}{\mu_0} |\mathbf{B}|^2 \right) \tag{1}$$
The "paradox" is if we use ...
- 1,289
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2
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4k
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How are the magnetic field lines in a electric dipole formed (step by step and graphically)?
The following picture shows how an oscillating electric dipole generates closed electric field lines step by step (it is common to find those picture in textbooks).
But how are the magnetic field ...
- 2,617
0
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0
answers
160
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How to derive the inclination angle evolution of a dipolar pulsar?
The spin-down evolution of a simple vacuum pulsar model is well known. Using the power output of radiation emission of a rotating magnetic dipole, we get the following equation (assuming that the ...
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3
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2
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2k
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What happens when an electric dipole is placed in a uniform magnetic field?
I am currently trying to understand the classical consequences of more than one charged particles in a magnetic field. So a thought experiment which came to mind was an electric dipole being placed in ...
- 620
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1
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362
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What is the strength of magnetic flux density inside a magnet?
I am trying to simulate the magnetic flux density in 3D space. I can get B by following model which is a dipole's contribution to the magnetic field at a point.
However, the strength of B is wrong ...
- 101
5
votes
3
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4k
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Why does magnetic force vary in proportion to the cube of the distance instead of the square?
Magnetic forces vary from gravity and electromagnetic radiation (such as light) in that gravity and radiation diminish by the square of the distance from the source, but magnetism diminishes by the ...
- 4,494
0
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1
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242
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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 ...
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1
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1
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118
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Relationship between exp(1/z) and the magnetic field
I will preface this by saying that I'm a math student, so I know a fair bit of math but almost no physics beyond what is learned in a first year undergraduate course.
I was recently looking at this ...
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