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0 votes
0 answers
24 views

Length of helix in one time period [closed]

How to find the length of a helix in one time period? In the case of a particle suspended at the origin and a magnetic field along the $y$ axis we know that the time period will be equal to $2\pi/aB$ ...
kartik Yeole's user avatar
0 votes
1 answer
32 views

Internally, what defines whether a material is magnetically hard or soft?

I know that magnetically hard materials hold magnetic fields (magnetic moment alignment) for longer, while soft metals do not. However, what, internally, causes these properties to arise?
Flamethrower's user avatar
1 vote
0 answers
32 views

Confused between induced emfs

We know when flux of B changes an EMF is induced in loop And also when a rod moves in mag field Potential difference between its ends is also produced. So is this ques while writing Potential equation ...
Macron's user avatar
  • 11
-2 votes
0 answers
30 views

Self-inductance of $N$ turns coil to current loop [duplicate]

I saw nice problem, that tricked my mind. The system is: Given that the coil has self-inductance of $L$, with diameter $D$ and $N$ turns. Now we take the coil, and open the turns to form single loop. ...
MrKnowOne's user avatar
0 votes
2 answers
71 views

Magnetic flux and number of turns

The number of windings is not written in the magnetic flux formulas in high school textbooks, but I come across articles saying that the number of windings affects the magnetic flux formulas. Is this ...
cem tansoylu's user avatar
0 votes
1 answer
32 views

Magnetic energy terms of system of three circuits

Say we've got a system of coplanar circuits like in the picture with same electric current flowing through them We know that a system of circuits has magnetic energy $$\mathcal U_{\,\mathrm m}=\dfrac{...
Conreu's user avatar
  • 296
1 vote
1 answer
37 views

How does any changing magnetic field induce voltage?

Hopefully the title puts in well enough; a charged particle moving in a magnetic field experiences the Lorentz-Force. If this occurs in a wire and part of the circuit is outside the B-Field then a ...
Robbe's user avatar
  • 347
1 vote
3 answers
78 views

Work done in a moving conducting bar and in a Faraday disk

I deeply apologize for my ignorance, but I am asking this since I still can't seem to grasp what my teachers relayed to me a few days ago about two exercises that I solved in an intrinsically wrong ...
Some random guy's user avatar
1 vote
0 answers
32 views

What is the reletive permeability of structual steel?

Help, i need to know what the reletive permeability is of a few materials (listed below) but i can not find the data on the internet. Does annybody know the data or where i can find it? -s235jr -...
laurent's user avatar
  • 11
0 votes
0 answers
59 views

Emf induction in a conducting coil placed in a variable magnetic field

Consider a conducting coil placed in a variable magnetic field. By the laws of nature, an emf will be induced in the coil. Between which two points is the emf induced in the coil? If we consider it to ...
KeSHAW's user avatar
  • 45
0 votes
1 answer
50 views

Straight wire cutting magnetic flux - Faraday's law

For a straight wire moving perpendicular to a uniform magnetic field in velocity v, $$ε=\dfrac{\Delta \Phi}{\Delta t}=\dfrac{BLv \Delta t}{\Delta t}$$ So the induced e.m.f in the conductor as it moves ...
Maxine's user avatar
  • 23
6 votes
3 answers
216 views

Ring Magnet with a wire in the middle

I have a very specific question concerning a system with a magnet and a wire. Consider a ring magnet with a magnetic field directed right through its center. In the center of the magnet is a wire, ...
Mo711's user avatar
  • 89
0 votes
0 answers
39 views

What is the induced electric field in a moving conducting material in a magnetic field?

I've been taught that the induced EMF in a conductor is the rate of change of flux in it, but Maxwell's equation $$ \nabla\times\vec{E} = -\dfrac{\partial\vec{B}}{\partial t}, $$ only states so for ...
Duta Kartvelishvili's user avatar
2 votes
1 answer
55 views

Does making a magnet move require more energy than a non-magnet?

I know that electric fields store energy, with their energy in an infinetesimal volume being proportional to $E^2$ at that point. I also know that a moving magnet creates an electric field (...
Hadi Khan's user avatar
  • 531
0 votes
0 answers
12 views

Self-induction in a permanent magnet

when a permanent magnet is moved in a coil, an emf is induced in the coil. so is an emf also induced in the magnet itself? and if not then why not. and if I replace this permanent magnet with a ...
Safa yousif's user avatar

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