Magnet Definition and 868 Threads

I'm trying to simulate a Magnetostatic problem. In my model there are two coils and a reciprocating permanent magnet. I defined a parameter, Xpm (movement of permanent magnet) in x direction to imply the reciprocating movement of permanent magnet like a piston. Xpm = f(t). I defined "t" as sweep...

Hi. My question is described in the summary. I'm seeking some advice. The Reissner-Nordstrom solution for charged spherical bodies seems to indicate that electrostatic fields will be a source of gravitation. I've not seen anything similar for magnetic fields but I can't imagine how it could be...

I have been trying to calculate the magnetic flux thought a single loop of wire occurring from a magnet (meaning it has a nonuniform field), so I have the following equation: Φ=∮BdAcosθ Now my problem is that I do not know how to calculate the magnetic field strength (B)of that magnet (which...

I thought of few scenarios and they ended up as follows: The ring must have an induced current. Due to the symmetry of the ring, if one part of the ring feels a force, the part of the ring radially opposite this part will feel a force opposite in direction, since the current will be opposite in...

Hi, I'm studying how distance affects the impact of magnet collision. Would like to have some idea before conducting experiment. Imagine 1. holding a magnet at different distance near a fixed metal 2. release the magnet; the magnet attract and collide to the fixed metal Will the distance affect...

Charge will experience a rotating magnetic field around it. What will be electric field ( If any ) at the centre, generated by rotation of magnet ?

Hello all!, first post here we go! I was hoping someone could answer a question for me because I can’t find the answer online. Or maybe point me to a magnetic field’s for dummies website.. I’ve been playing with a neodymium magnet shaped like a coin for a few days (yes easily occupied) and...

As we know the magnet will stop to repel each other after some time, is there any formulae to calculate when it will stop? From common sense, how long magnet will stop repel each other? 1years?

I was wondering if the strength of a bar magnet constructed from smaller magnets would increase if the smaller magnets were placed in an arrangement where the poles were opposing each other. I was able to jam 2 rare Earth magnets together with opposing poles and measured a higher magnetic flux...

I've been told that if you drop a magnet through a coil the induced emf and flux graphs would look like this: I understand that when the bar magnet is in the middle of the coil the emf induced is zero as flux change in top and bottom is in opposite directions but why is effective flux maximum...

Ok so here is something that made me scratch my head and I still can't come to a final conclusion. The basic idea is seemingly simple. You have permanent magnets attached to a core, the field lines close on both magnets through the core, so far so good. but the core also has electromagnets , put...

Is it possible to demagnetize a magnet using alternating current? How does this happen? And is direct current also possible?

Basically, I need to generate the strongest possible field at 10 cm from a circular magnet, in its central axis. I hesitate about what buying. For example, the following magnet has a large diameter of 90mm and is flat, with a suction of 250 kg. This other magnet has a smaller diameter of...

If you take a horseshoe magnet and fuse the north and South Poles together (without destroying the magnetic field) would you have a “pole-less” magnet? And if so, what special properties would it have(other than other magnets)?

Apart from the trivial elements of the motion equation (m z'' = -kz -mg), I am required to find the force produced by the Eddy currents induced by the moving magnet. To do so, I calculated the magnetic flux through the hole plate: For a magnet: Bz=μo m 4π. 2z^2−r^2/(z^2+r^2)^5/2 so Φ = a→ +∞...

No idea where to start

So, as far as I think I understand, an electron that passes through a Stern-Gerlach magnet, will not have a value for its spin until that spin is measured? Does that mean the electron has no position (as given by the SGM) until measured, or that the electron does not even exist until measured?

so I toke three magnet, two smell magnet and big one so the big one is attractive both of small onces so it order like -(+-)+ . I toke the small magnet close to the edge of the range magnetic and lift it so the magnetic field is preventing it from falling because the magnet is trying to flip...

Say I've got a magnet flying through empty space in a homogenous magnetic field. The magnet precesses and flies in a straight path. Now make that magnetic field inhomogenous. The magnet precesses and flies in a curved path. What I can't figure out is why the path is curved. It is because...

I don't really know but if I were to guess it would be based on how many turns are in the coil, the diameter of the coil and the flux of the magnet. Unfortunately I couldn't find a formula anywhere.

I was watching Jeopardy last night. In the Category "Magnet" was the following: "An 1845 letter from the 21-year-old future Lord Kelvin inspired this British scientist to show how magnetism & light are related" My guess: I was pretty sure this was wrong, based on the 1845 time frame, but I...

I have an ordinary switchable magnet for holding tools to a lathe. It's like a magnetic force gearbox, but I can't quite understand the force multiplication. When placed on a steel surface the switch force is approximately ~5N on both finger and thumb at 1.5cm radius acting over a 3cm arc...

If you hold a bar magnet in the middle of an empty volume and put a gauss meter in front of a pole, there is evidently a measurable magnetic flux, so there is a magnetic circuit there. What is the reluctance of the whole circuit, not counting the bar magnet itself? How do you work that out? Is...

The magnet being used % magnet dimensions [m] d = .0127; r = .00238; %mass of magnet [kg] m_w = .0017; % other constants u_0 = 1.26E-6; % permeability of free space constant T m/A g = 9.81; % gravitational constant in/s^2 %coil properties [22 gauge wire] [m] a = .00635; %radius w =...

The moving magnet and conductor problem is an intriguing early 20th century electromagnetics scenario famously cited by Einstein in his seminal 1905 special relativity paper. In the magnet's frame, there's the vector field (v × B), the velocity of the ring conductor crossed with the B-field of...

Suppose I have a finite sized cylindrical bar magnet of radius $a$ and length $b$. It is coaxial with the $x$ axis and moving from $-\infty$ to $\infty.$ A circular closed wire of radius $r>a$ is in the $y-z$ plane with center at the origin. When the bar center of the bar magnet passes through...

I have measurements of period time and distances that's all: T (sec) D (m) 0.9 0.008 0.91 0.009 0.97 0.01 0.98 0.011 1.06 0.012 I thought about adding the magnetic force like: T=2π*√l/(g+x) but have no clue how to integrate the distance there, I don't know even how to start...

If I have a block of N52 and I want to make it's magnetic field as strong as possible, would a Halbach array give me this maximum or is there a different pole arrangement/array that would provide this? I'm thinking for the use in a motor, so the field doesn't have to be large. A close field...

I wandering if the size of magnet or if there is vacuum or not change the range of magnet

To be more precise the generator has to be able to produce around 1.5 Watts from a person spinning its axis, which is why I was thinking of putting a gearbox in my design but I need to know how much Torque would it take to spin the axis and at what rpm would the generator be effective.

I am a real person. I ll do my best not to ask dumb duplicate questions.

Hello, Today I am wondering if anyone can help me quantify the strength of the magnetic field created by a permanent cylindrical magnet. I have been able to find equations online for the strength of the field within the z axis, (ie. the longitudinal length) but I would like to know the strength...

The red arrows correspond to the areas the solenoid will be moved too

i have a neobydium magnet of grade n40 , the diameter of magnet is 15mm and thickness is 10 mm , now i want to calculate the pull force between this magnet and a steel plate when there is no gap between them ; & in second case i want to calculate the pull force when i put a 0.15mm copper plate...

Summary: Considering a charged particle moving through a magnetic field, what forces does the particle exert on the magnet that is causing it to deflect? Hi all, probably a dumb question, but what force(s) does a charged particle exert on a magnet as it passes through it's magnetic field and...

What would happen if a coil it’s exposed to a moving magnetic field with only north poles? Coils being exposed to only North Pole. Will produce alternate current or nothing?

Consider the following, a magnet and a charge is attached to a platform, which is constrained to move only up and down direction. Now, if magnet is moved towards charge, due to changing magnetic field, an electric field will be created. This electric field will impart force on charge. since the...

Summary: For the same mass of copper wire, would more turns or greater thickness create a stronger magnetic field from a coil? So I am attempting to make a brush less DC motor, and I am wondering whether the coils would create a greater magnetic force if there are more turns or if the wire is...

Summary: Does a static magnetic field affect a weaker pulsed magnetic field close by? If you have a static magnet close to a low level pulsed electromagnetic field, will the static magnetic field influence the pulsed field if the static magnetic field is the same strength or stronger than the...

As stated in the link below, when a magnet bar (or a current loop) is placed in an external magnetic field it (its magnetic moment) becomes aligned with the magnetic field while an orbiting electron would have precession with Larmor frequency. What is the reason for these different behaviors...

Why a magnet bar would become aligned with the external magnetic field while a magnetic moment would precess around the external magnetic field?

Hi all, I'm fairly new here. I'm currently designing an as-homogene-as-possible permanent magnet for low-field NMR and similar experiments. I'm on a fairly tight budget, and having finally found pole pieces for my magnets, I got them even though they have a small saw cut in the edge. approx. 5...

I got the opportunity a while ago to play around with a magnet floating above a superconductor cooled with liquid Nitrogen. The magnet was a little cube, and I spun it with a pair of tweezers. I was surprised at how quickly it stopped spinning, it seemed to stop much quicker than could be...

I wondering if it is possible to create an electromagnet that has a diameter of 0.5 cm that can generate 75 - 100 lbs of pull force. I took physics in college so I have a basic understanding of how magnets work, but I don't have any practical knowledge. I don't know what is feasible. I found...

Can an everyday magnet disturb a ray of light. I have seen many answers online saying no, and some saying yes, but only if the magnetic field is large enough.

So I'm kinda stumped. I'm assuming that since ##\vec{m}||\vec{B}##, the x and y components of both are zero. But I'm unsure how to take this further.

for a infinite length length of current, only consider a part of it, is the direction of magnet field of a ring on the mid vertical plane the same magnitude and along the tangential direction? and for a closed surface , if the flux is 0?

hi all I am going to do a project in ansys maxwel, actually i need to add a magnet and i know i have to do it with add material. my magnet is NdFeB . i give the material from net, actually i can not valid them because they are different in value. I need to calculate Mu(permeability ) and I nedd...

In attempting to make magnetized neodymium powder, I grinded neodymium magnets into a powderusing a belt sander. However, I found that the magnetic properties of the neodymium had decreased substantially. It would appear that any attempt to grind the magnets into a powder using this method seems...