New answers tagged magnetic-fields
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Does the Earth's Magnetic Field Affect Sleeping Position?
There seems no direct link between magnetic field and the human body.
A short period exposure to strong magnetic field is harmless (MRI)
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Ampere's law on solenoid, using a circular loop
The previous answers explain what is happening, I will just throw in some equations for completeness. You can model your solenoid as a cylindrical sheet of current. For an idealized solenoid, the ...
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Ampere's law on solenoid, using a circular loop
You've discovered an important, real feature of coiled wire solenoids. Ampere's law is working correctly, and it shows that the magnetic field outside is indeed not zero. Instead, even for an infinite ...
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Ampere's law on solenoid, using a circular loop
So, you're just doing:
$$ \epsilon \rightarrow 0 $$
but never getting there, and then asking:
"Hey, why is $\epsilon \ne 0$"
The field outside the solenoid is not zero, it is only zero if:
...
- 35.4k
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How can I calculate the magnetic field of a plasma?
Magnetic fields created by currents running in a plasma are no different than those created by currents carrying wire.
You need to know the current density in your plasma and then apply Ampere's law. ...
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What effect do two perpendicular magnetic fields have?
Maxwell's equations are linear, that means:
The magnetic field of two loops of currents is then sum of the magnetic fields of each loops of current.
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Using opposing magnetic fields to find center of an area between 2 magnets?
Yes, if the plumb bob is on a hinge-like support (so it cannot
deflect out of a single plane of motion) you can affix magnets
to it, and around it, to cause it to seek center by magnetic repulsion.
...
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What make the energy transition in NMR?
You are talking about MRI not NMR spectroscopy. NMR requires only 1 field. MRI uses more complicated magnetic field to produce 3-d image.
You only need magnetic field for Zeeman effect, with electric ...
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Quick question regarding Larmor precession and bar magnets
https://en.m.wikipedia.org/wiki/Ferromagnetic_resonance: ‘ Ferromagnetic resonance, or FMR, is coupling between an electromagnetic wave and the magnetization of a medium through which it passes. This ...
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Visualizing or Interacting with the Higgs Field
Well, if you have a scale and step on it, it will tell you your weight.
Let's say your weight is 100kg (please let me know if you need modification), then around 1kg is coming from the quark's mass ...
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Why did static magnets make ice melt faster?
The magnets are metallic, so they are better heat conductors. Just repeat your experiment with some non magnetic material like copper, it will melt even faster. So it has nothing to do with magnetism....
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Moving charge to define magnetic field
1 - A particle doesn't have to be in motion to define a magnetic field. A stationary particle will just create a null magnetic field (see Biot-Savart law).
2 - No. See Lorentz's force $\vec{F} = q\vec{...
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Magnetic field due to power supply lines
During geomagnetic storms there will be slow-varying currents induced in the power lines. Often these currents are so high that they cause severe damage in the power station [see: "March 1989 ...
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Magnetic field in different frames
"If I move at the same velocity as that of a charge Q, I wouldn't be able to feel its magnetic field because it is stationary with respect to me." This is not true. If you Lorentz ...
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Relation between Earth's and Sun's magnetic axis relative to their paths of travel and relative to each other?
From the Wikipedia article Earth's orbit,
The magnetic pole is more complicated. First the magnetic north pole is misnamed from a physics point of view. The north pole of a magnet points north ...
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Why is flux of magnetic field always zero for closed surfaces?
If it holds, the local form of the of the "non-existence" of the magnetic monopole is the Gauss' law for the magnetic field,
$$\nabla \cdot \mathbf{b}(\mathbf{r},t) = 0 \qquad \forall \, \...
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Why is flux of magnetic field always zero for closed surfaces?
All these things are certainly true, but that is exactly the beauty of working in the differential notation of $\nabla \cdot \overrightarrow{B} = 0$. With the divergence theorem (https://en.wikipedia....
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Magnetic static field simulation software to model metals in Earth's magnetic field
This is a more complex problem than you might think. Assuming a linear B-H relationship with no hysteresis makes it slightly less complex. The only analytic solutions I know of are for sphere and ...
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