Questions tagged [magnetic-moment]
The magnetic moment of a magnet is a quantity that determines the force that the magnet can exert on electric currents and the torque that a magnetic field will exert on it. A loop of electric current, a bar magnet, an electron, a molecule, and a planet all have magnetic moments.
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Absolute value of the total magnetic moment of an electron in an atom
The magnetic moment operator being
$$\mu = -\frac{\mu_\text{B}}{\hbar}(L+2S),$$
a direct evaluation of its absolute value would be
$$|\mu| = (\mu^2)^{1/2} = \frac{\mu_\text{B}}{\hbar}(L^2 + 4S^2 + 4L\...
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How do we define the distance between two current distributions in the dipole force law?
I was reading Electromagnetism by David Tong. In Chapter 3 (Page 60), he deduced $$\mathbf{F} = ∇(\mathbf{B} \cdot \mathbf{m})\tag{3.28}$$ by Taylor expanding $\mathbf{B}$ around a certain point $\...
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Electric dipole moment and magnetic moment of atom [closed]
From Quantum mechanics by McIntyre chapter 14.3.
He describes electric dipole interaction. I have not studied electrodynamics so I never heard of the electric dipole.
What is the difference between ...
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How to understand the action of a stationary particle?
I am learning about action and how light takes all possible paths from point A to point B. How do we understand the action of a stationary particle like an electron? How do we understand the concept ...
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The Fundamental $B$-$H$ Relation in Hard Magnetic Materials
I'm confused about the most fundamental and universally correct relationship between the magnetic fields $B$ (magnetic flux density) and $H$ (magnetic field strength) inside a hard magnetic material. ...
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Energy balance in adiabatic demagnetization
Adiabatic demagnetization is a standard process for cooling paramagnetic materials.
So let us consider a paramagnetic material with a magnetic moment $M$ induced by an external magnetic field $B$. If ...
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Will a magnet levitating in an actively-controlled field always have a "free axis" of rotation?
I recently saw an advertisement for a fun gadget: a 20-sided die levitating (via active magnetic control) over a pad (with an array of electromagnets, I assume). In the video demonstrating the gadget,...
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How does a magnetic field generate and spread?
I recently studied electron spin and magnetic fields. But I'm unable to understand how the magnetic field arises from this spin
All answer I have gotten are that this is a property of electrons
But I ...
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What symmetries constrain the magnetic dipole moment to be proportional to angular momentum?
While working on calculations regarding dipole moments in quantum dots, I noticed an interesting difference between the form of magnetic and electric dipole moment operators in quantum mechanics (bold ...
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Why does a magnetic moment with a gradient generates a net-force (besides a torque)?
I am trying to understand the Stern-Gerlach experiment and, for that, I need to understand why is it expected that a magnetic field with a gradient in direction z will generate not only a torque that ...
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What makes three generations of lepton so different in anomalous magnetic dipole moment?
I've read the questions discussing the differences among electrons, muons and taus. However, I am perticularly interested in their anomalous magnetic moment which seems not to be discussed in previous ...
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How exactly does the exchange interaction cause ferromagnetic ordering?
I would be very grateful for some feedback on if the following understanding of how ferromagnetic ordering comes about is correct or not:
The consequence of the exchange interaction is that the energy ...
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How do magnetic domains realign?
I'm familiar with the origin of permanent magnetism, in which outer shell electron magnetic moments align between atoms in atomic structure, eventually in a large scale region or domain in the solid.
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Eddy current levitating force?
Hi,
Is it convenient to ask the following question about eddy current levitating coil?
Suppose the rms value of ac sinewave current current in the
coil/solenoid is kept constant ,
but the frequency is ...
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Magnetic moment of a current carrying closed loop
I understand that the magnetic moment of a current carrying closed loop is given by the cross product of the current I and area vector.
It will be perpendicular to the plane of the loop. But I don't ...
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