Hi,
I know, not another one, but I'm a more practical/engineering than scientific type - I need some tangible thing to learn stuff, so bear with me :)
Let me say hello first :)
The general idea was to model movement and electrical stuff with diff equations and do the hard part with femm. The...
Why is this stainless steel ferromagnetic while that one is non/paramagnetic, how's each proportion of them and what's its key difference that'd determines such the distinction?
Hello all!
I have a earring project with magnets involved but no magnet expert involved :( Here are a few stupid questions I hope someone can help us with!
BACKGROUND:
We are designing magnetic earrings. The earrings are meant to clamp the ear with 3 different levels of pressure. The magnetic...
I have thought about the following
##\oint \vec{H}\cdot d\vec{l}=0\Leftrightarrow H_{int}(D-h)+H_{ext}h=0\Leftrightarrow (\frac{B}{\mu_0}-M)(D-h)+\frac{B}{\mu_0}h=0\Leftrightarrow M=\frac{D}{D-h}\frac{B}{\mu_0}## but (supposing what I have done is correct) I don't understand which value of ##B##...
Hellooo
I have another questions about that fact that we have only a few solids that are ferromagnetic. In ferromagnetics i also read a few time ago it is important to consider 2 things about the reason why there is no magnetizaion. And i don't really understand both reasons, so i hope you can...
As one know, the force on mangnetic dipole in magnetic field is
$$ \vec F = (\vec p_m\cdot \nabla) \vec B_0$$,
where B_0 -- external field.
Let consider a some magnetic matherial with permeability \mu. The magnetization of matherial is $$M = (\mu - 1) H$$ (in SI units) and by deffinition $$M =...
A complete table of the ac susceptibility ## \chi_m ## of various ferromagnetic materials, where ## M=\chi_m H ##, is something that I have had trouble finding in a google of ferromagnetic materials. In what I have been able to come up with to date, there is quite a spread in the values of...
Hi Everyone -
I have a classical E&M physics problem that I've been tearing my hair out over. It relates to how ferromagnetic materials boost the field strength of a non-uniform magnetic field. My takeaway from college physics class was that (assuming there's no saturation in the material) the...
Hello everyone!
I want to know how to compute the force applied on ferrous inside a non-uniform magnetic field, to make it easier, let's assume that the field direction is constant, and the magnitude decreases linearly.
Now, I know that ferromagnetic material inside a magnetic field will...
Hi people,
In my college laboratory we were assigned an experiment to measure the hysteresis curves of a certain ferromagnetic material at different temperatures. Sounds simple, right? Well, the block of Monel 400 we chose did something weird.
We cooled it down to about -200°C and set about to...
Homework Statement
There are several parts to this question, however I could complete these parts. It is just an equation used in the prior part to the question that is need to solve this:
If we define \begin{equation} \sigma_{n}^{-}=\sigma_{n}^{x}+i\sigma_{n}^{y} \end{equation} and with the...
Homework Statement
We have a very long ferromagnetic cylinder with square cross section, with side length a. Cylinder is homogeneosly magnetized over his volume so that the magnetization vector is parallel to the axis of cylinder. Cylinder is in vacuum. Find the current appeared in the cylinder...
Curie temperature for magnetite is 858 C, for iron 1043 C. Duralumin melting point is about 630 C. Does this mean that if I take a small silicone mold, place a magnet underneath it, add ferromagnetic powder to the mold and then pour molten aluminum in, I will get the aluminum detail with...
Now after applying and removal magnetic field H=0 there will be residual magnetic domain in XYZ directions
Is the Heisenberg Model at very low temperature express about the energy of the system with higher accuracy than Ising Model in the previous case ?
and at high temperature is the Ising...
Homework Statement
The following coil-wound core (core length = L , Gap length = lg, cross- sectional area = A , core permeability = only hysteresis graph is given, N = N turns) is driven by a Voltage source, is known that the current in the coil is 60hz AC.
Determine...
Hi, I've been thinking about how to calculate a permeability curve, I thought this would be an easy to find online but unfortunately I haven't had any luck.
From what I can graphically see below:
It appears to me that mu for a ferromagnetic material is proportional to the derivative of B vs H...
Hello!
I am trying to understand a few properties of the ferromagnetic powder.I could not get the answers to these questions on the web, since any kind of phrasing i used, popped up search results that related to iron powder or ferromagnetic powder, which are manipulated and shape-shift using...
Hello everyone. I'm not entirely sure if this is the right section to post this question in but if it isn't, then I apologize.
I'm studying for a test in E&M and I've come across a topic that had me thinking and I'm not quite sure if the explanation I'm thinking of is entirely true.
Please...
What makes Fe, Co and Ni ferromagnetic compared to all other metals (with exception of Gd, Dy and some exotic alloys according to Wikipedia)? If other ferromagnetic metals just have lower Curie temperatures then why is it so?
Sub-question:
In pure metals is there any correlation in magnetic...
I have came up with a theory, it could be completely wrong or not but i had the idea of ferromagnetic decomposition and what i mean by this is breaking a ferromagnetic object apart (such as iron) using magnetism. Is this possible or not?
Hi,
My interest in physics is relatively new and recently I've been trying to figure out the answer to what is probably a simple question. Here it is; if one is using an AC EMF meter to read the time varying current from a man-made electromagnetic field, will brandishing ferromagnetic...
Hello. What oscillating field strength, in tesla, is required to cause the magnetization vector of a ferromagnetic material to precess with a fairly large angle at its resonance frequency? I can't find this number anywhere!
Hi,
I am doing my PG. To select a topic for my mini project, I select the topic "Ferromagnetic thin films" Probably I will be covering it's properties, fabrication and applications at some basic level.
So what is the problem is I have no one to guide me here as I am far away from the...
Hi,
I am doing my PG. To select a topic for my mini project, I select the topic "Ferromagnetic thin films" Probably I will be covering it's properties, fabrication and applications at some basic level.
So what is the problem is I have no one to guide me here as I am far away from the college...
Homework Statement
Electrons in a ferromagnet whose spins are oriented in the direction of, or opposite to, the internal magnetisation carry independent currents I+ and I−. This leads to the material behaving as though it has different conductivity σ+ and σ− for each of the two current...
Hello... I have a question: Physically why when a ferromagnetic is saturated the current is non-sinusoidal ( I'm taking the example of the magnetising current of a transformer). I know graphically and mathemeticalty why( from the hysteresis loop) but In reality what happens(I'm talking about...
I do not understand why ferromagnetic materials are more easily heated by an induction oven than a non/low ferromagnetic material such as copper or aluminum.
Are Eddy currents more easily induced into a ferromagnetic material than a conductor lacking a high ferromagnetic property? Why is it so?
Homework Statement
This isn't exactly a homework question so there aren't any data/numbers to work with. I just want to know what to do if there are two ferromagnetic cores inside a coil of wire, arranged as concentric cylinders. Or how to account for the air gap between the core and the coil...
Hello.
I know very few things about solid state physics, so my question is very basic.. I'm just searching for a clue..
Have some of you ever heard about, or imagine a way, of decreasing the permeability of a ferromagnetic material? Not by raising temperature, but with electric field or...
What is the spin direction of the electrons through the ferromagnetic material?
It will become parallel or antiparallel?
I was confused because the scattering rate and conductivity both depend on the density of state at Fermi level.
For ferromagnetic material, is it right to say that at the...
From another thread I think I understand that ferromagnetic material can exist any time, but dia & para magnetic materials exist only when there is an external field.
My overview is
Macroscopically ferro materials have to align their domains & can remain aligned when field is removed...
Dear All,
I have a paramagnetic material, its magnetic moment will saturate at magnetic field of 30 T (all spins align in the field direction). So shall I treat the high field phase as a ferromagnetic phase when I do electronic calculations?
Hello,
I'm building a coilgun and I'm confused. I understand that within a solenoid, the magnetic field is homogeneous. I've also read that a ferromagnetic projectile in a coilgun is sucked to the center of the coil. If the magnetic field is the same everywhere through the coil, what is...
For a ferromagnetic material in the hysteresis loop, when increasing field from H=Hc, its magnetization (M) will saturate. But if we decrease field instead, will M decreases clockwise according to the loop?
How can we make the ferromagnetic material back into the initial state (H=0, M=0)...
all i can find on the internet are the attractive and repulsive forces between 2 magnets... where can i find the relationship between distance and attractive force , between a magnet and i.e. a piece of iron?
Homework Statement
A toroidal shaped magnetic material of radius, a, and cross sectional radius R has a small transverse gap cut into it of length l. The toroid is uniformly overwound with a coil of N loops carrying a current I. Show that for a ferromagnetic material the field in the gap is...
Hi,
I have searched the web for a graph that shows the ferromagnetic properties of a metal like iron or nickel as they warms up to the Curie temperature - when the metals becomes non-ferromagnetic. I cannot find any good images or graphs that shows this very clear. I have been told that the...
I have been working on a transformer that has a potential difference out but no current. it uses of electron spin orbit to work.
here is a brief explanation with some references
i have uncovered that iron is unique in that each atom has a magnetic moment, that is each atom has a north...
Hello everyone. There is a little project I could use some help with.
I would like this done in a spreadsheet, so I can mess around with different values.
The Problem:
On one hand, I have a permanent magnet and, on the other, I have a ferromagnetic object. I want to find out the force...
I have a Nickel cylinder, 5 micron in diameter and 10 micron in length. I know the external field \vec{B} is 80 gauss, what is the formula for the magnetic dipole moment of this cylinder in the field?
Now I only have the formula for magnetic dipole of spheres, which is \mu = \frac{4}{3}\pi...
In the context of electromagnetic wave propagation in ferromagnetic medium, what is meant by magnetostatic spin wave? This terminology one came across in the wave modulation in ferromagnetic medium.
Thanks in well advance..
Hello
when we study electromagnetic ,it is easy to find force of a magnetic field on particle witch has electric charge (for example electron and ...) but what is force of magnetic field on ferromagnetic materials? for example if we put a cube of soft iron with a*a*a dimentions near a...
I've searched high and low among the vast archives of the internet and have yet to find any kind of formula regarding the magnetic field strength of ferromagnetic material (i.e bar magnet... etc). Does anyone know what/if there is one? As is B(r)=...?
Thanks
Hi everybody
The bands of up- and down-spins are split in the bandstructur of a ferromagnet. Does the part with the higher amount result in a net magnetization?
If yes, doesn't that mean, that electrons passing a ferromagnet, they align their spin in the opposite direction compared to the...
I searched around the forum and found no mention of this so I figured I'd bring it up. Acura has been airing these commercials ( http://www.youtube.com/watch?v=rnZ4EyKrLAI" ) that claim to use a ferromagnetic liquid instead of oil and then claim that it improves handling.
Is any of this true...