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Questions tagged [magnetic-fields]

For questions that utilize the concept of magnetic fields (commonly denoted by the letter B), or for questions whose answers likely involve magnetic fields. More specific than the [magnetism] tag, as questions about the phenomenon & theory of magnetism do not necessarily involve the discussion of fields.

For questions that utilize the concept of magnetic fields (commonly denoted by the letter B), or for questions whose answers likely involve magnetic fields. More specific than the , as questions about the phenomenon & theory of magnetism do not necessarily involve the discussion of fields.

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How can magnets be used to pick up pieces of metal when the force from a magnetic field does no work?

I learned that the force from a magnetic field does no work. However I was wondering how magnets can be used to pick up pieces of metal like small paperclips and stuff. I also was wondering how magnets can stick to pieces of metal like a…
sTr8_Struggin
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If you are vacuuming your carpet and you wrap the cord around your body do you become a magnet?

If you wrap an active electric cord around your body, do you become an electromagnet?
Shawn Anderson
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What is the difference between the magnetic $H$-field and $B$-field?

From Wikipedia: "The term (Magnetic Field) is used for two distinct but closely related fields denoted by the symbols $B$ and $H$, where $H$ is measured in units of amperes per meter in the SI. $B$ is measured in teslas in the SI." So, the two are…
Sergei Gorbikov
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Is Biot-Savart law obtained empirically or can it be derived?

There's already a question like this here so that my question could be considered duplicate, but I'll try to make my point clear that this is a different question. Is there a way to derive Biot-Savart law from the Lorentz' Force law or just from…
Gold
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If magnetic field lines don't exist, what are these iron filings doing around a magnet?

Obviously the iron filings can be seen aligning themselves along the virtual magnetic field lines produced by the permanent magnet, the virtual magnetic field line is made of electromagnetic field due to the alignment of electrons in the magnet but…
user6760
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4 answers

Is there an underlying physical reason why the Coriolis force is similar to the magnetic component of the Lorentz force?

I couldn't help but notice that the expression for the magnetic component of the Lorentz force, $$\mathbf F = q\,\mathbf v \times \mathbf B\,,$$ is very similar in its mathematical form to the Coriolis force, $$\mathbf F = 2m\mathbf v \times \mathbf…
dahemar
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Why doesn't light affect a compass?

In our daily life a lot of photons of visible light, infrared and radio etc move around us. We know that light is an electromagnetic radiation. So why doesn't that electromagnetic radiation affect a magnetic compass?
Bhavesh
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5 answers

What is happening when magnetic field lines snap or break?

In discussions of sun spots and auroras on Earth, magnetic field lines are often described as "snapping" or "breaking", with the result of releasing charged particles very energetically. My understanding is that field lines are just a visualization…
Robert
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Is there an intuitive explanation for why Lorentz force is perpendicular to a particle's velocity and the magnetic field?

The Lorentz force on a charged particle is perpendicular to the particle's velocity and the magnetic field it's moving through. This is obvious from the equation: $$ \mathbf{F} = q\mathbf{v} \times \mathbf{B} $$ Is there an intuitive explanation for…
Stephen Jennings
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4 answers

How are magnets held together, and why do they not explode?

Imagine we have a magnet (red side is the north pole, blue side is the south pole), and imagine two ways to split it. The first way: When we split it by separating the north pole from the south pole, we see that the two pieces are themselves dipole…
MaximusIdeal
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Why is there no magnetic field around a wire connected to electricity at home?

Is it true that an electric current that flows through a conductor creates a magnetic field around the conductor? If yes, then why doesn't the magnetic sensor of my mobile device react in any way to changes when I bring the device near to the wire…
Turkhan Badalov
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Is the presence of a magnetic field frame-dependent?

I do not have a strong background in physics, so please refrain from using complex mathematics in any answers :) I was on this site, and I read: When an electrical charge is moving or an electric current passes through a wire, a circular magnetic…
Cyclopropane
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Can someone please explain magnetic vs electric fields?

I've looked through about 20 different explanations, from the most basic to the most complex, and yet I still don't understand this basic concept. Perhaps someone can help me. I don't understand the difference between the electric and magnetic force…
user1299028
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Does a magnetic field do work on an intrinsic magnetic dipole?

When you release a magnetic dipole in a nonuniform magnetic field, it will accelerate. I understand that for current loops (and other such macroscopic objects) the magnetic moment comes from moving charges, and since magnetic fields do no work on…
Joss L
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Is Earth really a magnet?

I am a student of class 9. When I was going through magnetism and read that an earth is a magnet I got some doubts. My question is: is earth really a magnet? Doesn anyone have any proof that earth is a magnet? Is there a magnetic core at the center…
prayagdutt pandey
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