For questions that utilize the concept of magnetic fields (commonly denoted by the letter B), or for questions whose answers likely involve magnetic fields. More specific than the [tag:magnetism], as questions about the phenomenon & theory of magnetism do not necessarily involve the discussion of ...

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-1
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2answers
225 views

Motion of charge in magnetic field with drag force [closed]

Say you have a charged particle in a region that contains a fluid that will produce a drag force that goes as $F=-kv$ where $v$ is the speed and $k$ is some constant. The region also contains a ...
3
votes
2answers
777 views

Do two magnets stacked on top of each other repel/attract stronger than just one magnet?

In designing a switch, I made it such that it "springs" back via two neodymium magnets (one in button repelling one in switch). I've found the magnets are too weak and don't spring back. I've resorted ...
1
vote
1answer
193 views

How this linear Motor Shaft works?

I am trying to understand how this linear motor works: You can see a video here for more details. From what I know each permanent magnet consist a North and South poles so for a cylindrical magnet ...
0
votes
2answers
66 views

Coronal Mass Ejection and its effect on Earth's Orbit

Do CMEs (Coronal Mass Ejections) have an effect on Earth's Orbit around the sun? Given the the Earth and Sun are essentially two large magnets, one in orbit around the other. If so, how much of an ...
5
votes
1answer
150 views

How can steel shavings get magnetized while hole tapping?

I was tapping a hole yesterday with my uncle into a piece of soft steel. (A tap cuts threads on the inside of a hole, to accept a machine screw or bolt.) The tap was NOT magnetic! As I finished boring ...
0
votes
1answer
198 views

Does greater number of lines of force around the magnet imply greater magnetic field strength around it?

If we sprinkle iron fillings on a sheet of glass placed over a short bar magnet. The arrangement of iron fillings will be similar to the one shown above. Why do some of the iron fillings ...
0
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0answers
30 views

Opposite field's acting on a soft ferromagnetic material

To external fields(H, - H) not equal to each other are acting on that material. Based on the hysteresis loop what would be the result? The hysteresis area of that materials is very narrow(i.e easy to ...
3
votes
1answer
539 views

Axial forces on a solenoid windings

I understand that the windings in a solenoid experience a Lorentz force $\mathbf{f} = \mathbf{J} \times \mathbf{B}$, which tend to cause an outward pressure where $\mathbf{B}$ is directed along the ...
1
vote
2answers
794 views

1 Tesla electromagnet?

Is it possible to create a powerful electromagnet at home? With use of a ferromagnet it seems so... Using the following formula: $B(Tesla)= k\mu_0nI$. I understand some ferromagnet's like iron could ...
1
vote
4answers
201 views

Is voltage important when creating a magnetic field?

Would a DC circuit that has a high current and low voltage have a powerful magnetic field? I'm trying to create a powerful solenoid. In order to create a powerful magnetic field, I'm focusing more on ...
0
votes
0answers
46 views

Help in understand Magnetostatic Energy

$$E_{\mathrm{ms}} = \frac{1}{2}\mu_0 \int_V \mathbf{M} \cdot \mathbf{H}_{\mathrm{ms}} d^3 r$$ I can't understand this formula, what is the magnetostatic stored potential energy?! What does it show? ...
5
votes
1answer
196 views

Why Inox Steel doesn't interact with magnets?

My dad has a HUGE magnet on his workshop. I love magnets, and when I saw it, I asked him what it was for. His reply was: "I don't know why, but inox steel bolts don't get attracted to it, so I use ...
2
votes
1answer
362 views

How does repulsion and attraction of a magnet work?

How does repulsion and attraction of a magnet work? I have a hypothesis. We all know that repulsion works when people throw balls at each other. This is used as an analogy of how virtual particles ...
0
votes
2answers
370 views

Why is a paramagnetic material attracted into a magnetic field?

I want to start by saying I've seen this topic: Attraction and repulsion of Magnetic materials and its supposed duplicates and it hasn't helped me very much. In the book Introduction to ...
0
votes
0answers
43 views

Which is more energy efficient: optical demagnetization or heating beyond $T_c$,

What is considered more energy efficient? Current research show that the amount of energy used for powering a laser to demagnetize a material is quite small. However, the demagnetization is very ...
0
votes
0answers
87 views

Calculating repulsion due to eddy currents?

I have a conductive particle moving at a known speed through changing magnetic field (Permanent magnets attached to a rotating drum alternating north/south). These particles will have induced eddy ...
2
votes
1answer
82 views

$\hat{\imath}$ component of force exerted on an electron by a magnetic field?

The magnetic field over a certain range is given by $\vec{B} = B_x\hat{\imath} + B_y\hat{\jmath}$, where $B_x= 4\: \mathrm{T}$ and $B_y= 2\: \mathrm{T}$. An electron moves into the field with a ...
0
votes
0answers
41 views

Formation of magnetic field in an inductor

I can't really imagine the way the magnetic field would be created due to electron flow in an inductor. We say that in a straight current carrying conductor the magnetic field follows the thumb rule. ...
3
votes
1answer
256 views

Detecting EM radiation using android app

I wrote a simple android app that shows the magnetic field(using the magnetic field sensor in the phone) in the current location. When I place a two inch steel screw on the top of the phone (which ...
0
votes
0answers
63 views

Lasers can demagnetize ferromagnets?

How is it possible to demagnetize a magnet with a laser? Source: http://www.helmholtz-berlin.de/pubbin/news_seite?nid=13657&sprache=en&typoid And the paper: ...
5
votes
2answers
91 views

In a strong field, how long would it take for domains to align?

How fast is the rate of "switch" for the domains to align with an exterior field? Possibly in milliseconds? I assume it won't take much time since domains are very small, and they only turn from a ...
0
votes
1answer
106 views

H field of this magnet? [closed]

How can I know the magnetization force that this magnet applies to other ferromagnets? What is H(in Oe or A/m) of this strong magnet? From the site: ...
0
votes
0answers
83 views

Hysteresis loop of soft iron for different field strengths?

When calculating the work done to magnetize a material, what is the usefulness of coercivity in that calculation? If the material $Hc = 0.5\: \mathrm{A/m}$ or $Hc = 9 \times 10^5\: \mathrm{A/m}$? I ...
8
votes
2answers
237 views

What is the mechanism by which magnetic fields do work?

I've seen some conflicted answers to this question in texts and on the web, in the case of a dipole, for example. Do magnetic fields do work directly, or is it their induced electric fields that do ...
0
votes
1answer
982 views

Current induced from a magnet moving through a solenoid?

If we had a magnet we move it towards a solenoid a half sine wave current is induced when we make it move back, the other half is induced, inducing an AC current in the solenoid. What if the magnet ...
1
vote
1answer
86 views

How do virtual-photons curve in a magetic field?

From what I understand photons only move in straight lines unless reflected or refracted (other than influences from gravitational fields and their usual wavelike movement). And since they are a ...
0
votes
0answers
22 views

Calculating torque applied on domain?

How is it possible to calculate torque that is applied on a domain due to the magnetization force[H]?
0
votes
1answer
65 views

Why do some of the iron fillings arrange in a particular pattern when sprinkled around a magnet, instead of getting attached to the magnet?

My sir started a new chapter "magnetism and matter". Sir said that iron fillings form a particular arrangement when sprinkled around a magnet. I saw the figure in my book where it was shown the ...
0
votes
1answer
58 views

Magnetization force on domains after alignment?

When a domain is aligned to an exterior uniform magnetic field. There are no forces acting on it? Magnetization force = 0, and all other force?
0
votes
1answer
38 views

Want to achieve maximum magnetic force & find out the max point [closed]

Hi Sir/ Madam Want to achieve maximum magnetic force & find out the max point for this setting, want to know is the strongest magnetic force must in the 'dot' area ( middle poin of setting ) ...
0
votes
0answers
100 views

Solenoid core and magnetism

I understand the core of a solenoid can help increase magnetic field produced by a given current and every metal has a specified permeability $\mu$, but what if we had a hybrid core, say 50% iron ...
2
votes
1answer
182 views

Geometriclength and effective length

Why is effective length of a bar magnet shorter than its geometric length? Blockquote in a textbook, author wrote that, effective length is equal to 0.85 times geometric length. But didn't ...
1
vote
1answer
563 views

Calculating Magnetic Field Magnitude and Direction?

I am trying to find the equation for calculating the direction and magnitude of $B$ and/or $H$ at a distance from a dipole magnet but my searches are proving impossible. So far I have found the ...
0
votes
2answers
100 views

How Can There Be Magnetic Force Without Velocity [duplicate]

Suppose there is a space with constant magnetic field, and a charged particle is moving in that space with a constant velocity, ofcourse it experiences a magnetic force and gets deflected. But the ...
3
votes
2answers
1k views

Does changing the electric / magnetic field cause self-reinforcing induction of the other?

I understand that changing electric field produces magnetic field and changing magnetic field produces electric field. Are these produced magnetic and electric field produced due to one defined to be ...
3
votes
1answer
176 views

Simulate the magnetic field of magnet

I'd like to numerically simulate the magnetic field due to a cylindrical rare earth magnet of known dimensions at a bunch of points $\vec{r}=(x,y,z)$ from its origin. My goal is to be as accurate as ...
1
vote
1answer
860 views

Difference between B and H in magnetic fields?

I'm confused between them. Can someone explain the difference between them? Is $\vec H$ field ONLY relevant during magnetization or demagnetization? $\vec H$ is just that value needed to ...
0
votes
3answers
292 views

Creating a 2d magnet simulator [closed]

I need to create a "simple" magnet simulator, unfortunetely I have little to no physics knowledge. The best way to describe my idea is, imagine a hockey table. There's a disk and I need to throw it ...
0
votes
3answers
1k views

What is the use of this formula 1 Tesla = 1 Newton/Ampere/Meter?

What does Newtons/Ampere/Meter stand for? From this formula: 1 Tesla = 1 Newtons/Ampere/meter what can it be used for? To do what? Ampere/meter Is the same unit as a field's intensity H? Or what is ...
-5
votes
1answer
444 views

Tesla to Newtons [closed]

Is it possible to convert Tesla to Newtons of force? Or magnetization force H:(A/m) to newtons?
0
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0answers
58 views

How long do virtual photons exist for in the Sun's magnetic field?

The Sun's magnetic field goes all the way out to the heliopause which is a very long distance to travel and magnetic fields consist of virtual photons so how long do these virtual photons exist for to ...
2
votes
2answers
124 views

Must every magnetic configuration have a north and south pole?

Magnets have a magnetic north and south pole. Solenoids too have north and south pole from which magnetic fields comes out and goes in respectively. But is it that every magnetic configuration have a ...
0
votes
1answer
241 views

Coercivity of a ferromagnetic material?

I understand that coercivity is the field/force required to demagnetize/magnetize a ferromagnetic material. What if we had two opposite magnetic fields of different strengths values H acting on the ...
0
votes
0answers
171 views

2D Ising model simulations: Wolff algorithm acceptance probability with an external magnetic field

I have implemented the Wolff algorithm to simulate a 2D ferromagnet. It works by building a cluster of like spins and flipping them all at once to move quickly through phase space. In the case of no ...
5
votes
2answers
274 views

Why does earth's magnetic field change its direction?

I know that the earth's magnetic field is due to molten metal and ions flowing in its core. It has been found that the Earth's magnetic field changes its direction and it has even flipped once! But, ...
3
votes
3answers
307 views

Understanding the Ampere's Law

We want to study the magnetic field at point $P$. So, from the figure we take that: $\oint_{L_1} B\cdot dl=\mu_0 I_1$ $\oint_{L_2} B\cdot dl=\mu_0 I_2$ $\oint_{L_3} B\cdot dl=\mu_0 I_2$ The ...
1
vote
0answers
349 views

Current flowing through a square loop - Magnetic Field [closed]

A square conducting loop of wire of side $2a$ carries a uniform current I. Calculate the magnetic field at the centre of square due to the current in the loop.
1
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0answers
40 views

Lorentzforce and righthand rule [closed]

Figure 1: A spool is hung on a spring. A part of the coil hangs in front of a homogeneous magnetic field. The coil is incorporated in an electrical circuit. See Figure 1. the coil ...
0
votes
0answers
64 views

Oil Lamp Dynamics

Here is a photo of an oil lamp I am making. I am facing a few problems.first how its made. Its a glass bulb with a custom fit plug made out of aluminium.The bulb balances by way of a neodymium ...
0
votes
2answers
593 views

Ampere's law on a long wire with varying current density [closed]

On a question from my book: A long straight wire with a circular cross section of radius $R$ carries a current $I$. Assume the current density is not constant over the cross section of the wire, ...