Magnetization Definition and 84 Threads

  1. G

    B versus H field (and Magnetization)

    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...
  2. M

    Sphere with permanent radial magnetization

    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...
  3. B

    What Happens When a Magnetic Field is Applied to a Gas in a Vacuum?

    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
  4. E

    Work done by doubling the magnetization of a rod

    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...
  5. O

    Magnetization Dynamics: Modeling the Ferrite Core of a Joule Thief

    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...
  6. D

    The Hysteresis Loop of Raw Iron: Understanding Coercivity and Magnetization

    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...
  7. G

    Magnetization of water surrounding submerged non-magnetic wire

    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...
  8. V

    Relationship between B and H fields in cylindrical magnetization

    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...
  9. R

    Little Question about magnetization and heat

    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...
  10. B

    Magnetization in a rod bent into a torus

    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...
  11. L

    Effect of material size on magnetization

    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...
  12. L

    Calculating Magnetization for 2x2 Ising Model Lattice

    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...
  13. A

    Cylinder with uniform magnetization

    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 =...
  14. I

    Frozen-in magnetization in a long cylinder

    "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...
  15. J

    Magnetic field of a cylinder with magnetization M=ks^2

    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...
  16. M

    Total magnetization of an isolated atom

    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
  17. J

    Magnetization above Curie Temperature

    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...
  18. S

    Relationship between remanence (B_r) and Magnetization (M)

    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...
  19. X

    Magneostatics - hollow sphere of spontaneous magnetization

    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...
  20. H

    Magnetization of a material with linear susceptibility

    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...
  21. L

    Magnetization current is a steady current?

    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...
  22. I

    How do para- and dia- magnetics differ in terms of magnetization?

    How does magnetization of a magnetic depend from its form?
  23. G

    ZPF Absorption Rate in Magnetization of Electrons

    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...
  24. D

    Magnetization in Classical EM: Bound Electric vs. Magnetic Charges

    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...
  25. M

    What is the Relationship Between Magnetization and Ionization in Neutral Atoms?

    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"...
  26. V

    Finding the strobilization of the magnetization at sphrerical coordinates.

    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...
  27. V

    Why magnetization is a linear function of external field?

    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...
  28. I

    Magnetic field of an infinite cyliner of fixed magnetization

    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...
  29. S

    Finding Absolute Permeability from Magnetization

    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...
  30. N

    How Do Bound Charges and Magnetization Affect Insulators?

    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...
  31. M

    Magnetization of Permanent Spherical Magnet

    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)...
  32. Repetit

    What is Magnetization Current Density?

    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...
  33. D

    How Magnets Interact & What Happens to Magnetization

    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?
  34. H

    How Is Magnetic Flux Calculated Near a Current-Carrying Wire?

    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...
Back
Top