Magnetization Definition and 98 Threads

Hello, I've been stuck on this question for a few hours and I hope someone can help. Here is the question: "Consider two materials bismuth and aluminum with χ m = −20 ×10−5 and χ m = 2 ×10−5, respectively. Find the magnetization vector and the magnetic field in these materials when they are...

This thread coincides with a previous thread I posted on reddit: http://www.reddit.com/r/chemistry/comments/2g69vt/magnetohydrodynamics_internal_energy_and_system/ I'm trying to solve the following equation: U=TS-PV+HM. The problem is I'm having difficulty solving H delta M. I was told H is...

Homework Statement Consider a square slab of magnetized material with sides ##2a##, and thickness ##d##, as shown. The magnetization is not uniform: $$M = M_o cos(\frac{2πx}{ a}) \hat{z} $$b) Calculate the total magnetic moment of this object. How would you guess the magnetic field decreases...

I heard/read somewhere some time ago during my electromagnetism course that when rolling a piece of metal into a metal plate, the magnetization properties will vary depending on how you apply the outer magnetic field. For instance if you apply a magnetic field perpendicular to the "direction"...

Can a magnetization density that is compactly supported be the gradient of a scalar field? This question relates to magnetic resonance imaging where the signal depends upon the curl of the magnetization density.

Hello, attached is a picture of a cylinder magnet moving in and out of a coil, in a linear AC generator configuration. Below it, there are 3 possible configurations for the magnetization of the magnet (axially/diametrically/radially). Which of the 3 configurations will produce more voltage on...

Hi all, Recently I learned about magnetization I understand that you apply a magnetic field B, and that your magnetization M is proportional to the field ... H? Like so, \mathbf{M}=\chi\mathbf{H} What is the \mathbf{H} field, though? It is the 'auxiliary' magnetic field, but what does...

Homework Statement We have a sphere of radius a with permanent magnetization \mathbf{M}=M\hat{e}_{\mathbf{r}}. Find the magnetic scalar potential. Homework Equations $$\Phi_M(\mathbf{x})=-\frac{1}{4\pi}\int_V \frac{\mathbf{\nabla}'\cdot\mathbf{M}(\mathbf{x}')}{|\mathbf{x}-\mathbf{x}'|}d^3...

What happens if we apply a magnetic field to a gas in vacuum, (like H or He)?, do the atoms get aligned like in ferromagnetic material and produce in their turn a strong magnetic field?, if they don't, why so? Thanks

Homework Statement Picture a rod of length L with N turns of wire around it What is the work done when one doubles the magnetization? We'll assume the coil has negligible resistance. Homework Equations \mathcal M is total magnetization of the rod. M is magnetic moment C_c is...

I'm working on a project that involves a Joule thief. I need to model the magnetization process of the ferrite core of the toroid. With that I will be able to get an accurate picture of the flux change, which I can use to predict the induced emf based on the characteristics of the system...

For magnetization which can be written as \vec{B} = μ(o) (\vec{H} + \vec{M}) , how would it be expressed as a function of N (number density N atoms per unit volume), μ , magnetic-field Bo, T, and some constants (Boltzman's constant, Curie constant)? I have found similar set ups from different...

The "area" of the hysteresis loop depends on the coercivity, the coercivity of raw iron(Wrought iron) is 2 Oe(160 A/m). If 1 gauss = 103/ 4∏ = 79.58 A/m(I'm not sure about this, http://www.sste.mmu.ac.uk/users/shoon/pers_page/envmagn_tables_anal/Mag-Units-Tables-New.pdf(under "General working...

Homework Statement A long straight wire of circular cross section with radius R carries current I and is immersed in a large volume of water. The wire is non-magnetic. Calculate the magnetization M(r) in the water which has a susceptibility χm. What is the bound current density Jb(r) for s...

So I've been simulating a really simple geometry using ANSYS Maxwell. It is a cylinder only and I am looking at the \overrightarrow{B} and \overrightarrow{H} fields in order to see their relationship between them when the material is magnetized in the circumferential direction. I used a...

Hello, I'm new so i hope I'm not posting this question on the wrong section, anyway, here's the question: Is possible to magnetize metals with heat? I'm asking because today i found out that my scissors became slightly magnetic after being in touch with fire for a while (i was using them...

Homework Statement I can't figure out why there is no bound current in the problem 6 (very subtle hint boldfaced) is the pdf below: http://astronomy.mnstate.edu/cabanela/classes/phys370/homework/ps10.pdf Can anybody give me a hint as to why there should be no bound current The Attempt at a...

I'm a bit confused about the effect of the size of ferromagnetic material on the magnetic field it generates so I was hoping someone could explain it to me. The saturation magnetization is given by M = \frac{N}{V}*μ but this suggests that the magnetization is independant of the size of...

Homework Statement Calculate magnetisation for partition function ##Z=12+4\cosh (8\beta J)## for Ising model 2x2 lattice.Homework Equations F=-k_BTln Z M(H,T)=-\frac{\partial}{\partial H}(\frac{F}{k_BT}) The Attempt at a Solution For me it looks that magnetisation is zero. By just doing the...

It is not from my howework(due I'm not in the undergrad now), but it seems to be a very easy question I have to know answer to, but I fail to do so. Homework Statement I have to go from classical to quantum Hamiltonian via WKB method (and both to solve Schroedinger equation) It looks...

A short circular cylinder carries a uniform magnetization M parallel to its axis. I want to know what the divergence of M is. Using divergence in cylindrical coordinates I get that ∇\bulletM = 0. Now I was pretty sure of this result until I read the following in my book: "∇\bulletH =...

"frozen-in" magnetization in a long cylinder hi I am doing this problem from Griffiths EM book on page 272 (3ed.) An infinitely long cylinder of radius R, carries a frozen-in magnetization parallel to the axis \mathbf{M}=ks\;\hat{z} , where k is a constant and s is the distance from the...

1. Homework Statement [/b] this is griffiths 6.8 fyi. a long cylinder of radius R carries magnetization M=ks^2 \hat{∅}, k is a constant and s is the distance from the axis. \hat{∅} is the azimuthal unit vector. find the magnetic field inside and outside the cylinder. Homework Equations...

im trying to study an isolated atom(Boron) and i can't for the life of me figure out what to do with the total magnetisation, which is defined as : further more: what are these guys talking about? is this explained out in detail somewhere in ENGLISH for humans? cheers mechdude

Hi all, I'm preparing a talk about Curie Temperature, and looking for some Ms(T) graphs in the web I've found some of them in which the magnetization is not zero when T > Tc, (the dramatic change is obversable, so it is the Tc). But for T > Tc I expect complete disorder and no domains, then...

If I have an ellipsoidal disk, where the demagnetization constants Nd_{xx}>>Nd_{yy}>>Nd_{zz}. The disk lies on the y-z plane and easy axes are +z or -z. The energy of the system (just considering demag fields) will be U=Nd_{xx}sin^2\theta cos^2\phi + Nd_{yy}sin^2\theta...

Hi, I have scoured through scores of websites but haven't found a reasonable solution. The thought problem goes like this. Take any NdFeB magnet which is saturated say to B_r =1.3 T. Is there a magnetization (M) value that corresponds to the this remanence. I have been able to find a few...

Homework Statement a) A hollow magnetic sphere of internal radius a and external radius b, has a uniform spontaneous magnetization M per unit volume. SHow that the field strength in the internal cavity (r<a) is zero, and that the external field strength (r>b) is the same as that of a dipole...

Fairly simple question: If a highly permeable material (of any shape) is placed in a uniform magnetic field, will the material's magnetization density always line up with the uniform magnetic field, or do I have to take into account the fields that are created as the material becomes...

Homework Statement We have a very thin plate of single crystalline Ni (fcc). The plane of the plate corresponds to the (001)-plane of the crystal. The crystal has a quadratic shape and is cut so that the edges corresponds to the crystallographic [110]-directions. The shape anisotropy makes the...

In developing Mazwell's equations in media, we considered the total charge as consisting of free and bound charges and currents, so that ρtot = ρf + ρb and Jtot = Jf + Jb The bound current maybe furhter divided into magnetization and polarization currents Jb = JM + JP ,expressed in terms...

My question is really basic, and I've ended up getting a bit confused because of it. My understanding is that magnetism of a material is based upon the intrinsic electron spin, the rotation of the electron around an atom, and the movement of electrons within a material, i.e- current. So...

How does magnetization of a magnetic depend from its form?

Homework Statement Just basically want to see if my algebra is ok. Homework Equations All are relevent. The Attempt at a Solution Calculating Rates in Magnetic Moments to Predict Period Interaction Between a Fermion and the Zero-Point Field First we must identify the net...

I have been trying to remember if in classical EM it is equivalent to describe magnetization through bound electric currents A. \vec{j_b} = \nabla \times \vec M \vec{k_b} = \vec M \times \vec{\hat{n}} OR bound magnetic charges B. \rho_b = -\nabla \cdot \vec M \sigma_b = \vec M \cdot...

I'm interested in the question of what strength magnetic field you need to fully or partially ionize a neutral atom. I'm fairly sure this is possible but I'm not very familiar with quantum physics, atomic physics, solid state physics, and so on. I'm familiar with the "classical analog"...

Plz Help: How to calculate magnetization in SSE method?? I need help from someone experienced with Stochastic Series Expansion algorithm. I'm working on SSE algorithm for lattice of isotropic Heisenberg spins and it works fine, well, mostly. I have nice values for energy and heat capacity...

Homework Statement If the magnetization of a sphere is: \vec{M} = \hat{\phi }\frac {r}{R}sin\theta M_{o} How much are the captive streams: J_{b}=\vec{\bigtriangledown }\times \vec{M} K_{b}=\vec{M}\times \hat{n} The Attempt at a Solution I find that the first is: J_{b} = \frac...

Homework Statement A bar of soft iron of cross sectional area A and relative permeability μ is bent into a ring of radius R. The bar is wound with n turns of a wire carrying a current I. Deduce a value for the magnetic field in the iron, explaining your assumptions. (b) A narrow gap of...

It is strange that the material magnetization is in linear proportion to external field because I see a positive feedback: The external field orientates the atoms. This increases the magnetic field, and, in turn, the increased field forces more and more atoms to align. The process goes on...

I'm taking a second year undergraduate course in electromagnetism and have a question that has arisen in the course of my studies. I'm normally reluctant to seek help on such matters, but this question has caused me a lot of grief. The question is as follows: An infinitely long cylinder...

Homework Statement I am doing a project for which I am learning some aspects of electromagnetism by myself, so you can imagine how lost I am. Well, not completely: I was searching for a ferrite with high permeability as a core material. I learned how the octahedral and tetrahedral sites and the...

Hi all. I was thinking of something: Bound charges in an insulator arise because of the polarisation, so even though we have bound surface and volume charges, an insulator will still be electrically neutral. I was trying to apply this line of though to a magnetized object. Here, the...

Consider the degenerate electron gas in a metal as a mixture of two gases of spin-up and spin-down electrons, respectively. when a small magnetic field B is applies, a few of the electrons reverse their spins so as to maintain equality of the chemical potential in the two mixed gases. For T = 0...

Dear all, 1) For a spherical permanent magnet, the magnetization M is defined to be pi/4u0*Br*d^3. My question is: if I attach 4 such spherical magnets together, would the magnetization simply be 4M? Where (website) can I find a good reference for these type of material? 2)...

Can someone explain to me what the magnetization current density (given by the curl of the magnetization M) and surface magnetization current density (given by the vector product between M and a surface normal vector) are? I have a book on electromagnetism but it doesn't really give a good...

It is well known the magnetic force cannot do work. What causes a magnet to move in the precense of another magnet? Does the magnetization of the two magnets diminish in the proces?

Find the magnetic flux crossing the portion of the plane theta = x/4 defined by 0.01 m < r <0.05 m and 0 m < z < 2 m. A current of 2.50 A is flowing along z-axis along a very long wire. in drawing the picture i know that there is a long thin wire with a current of 2.5 amps flowing...