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Questions tagged [magnetic-fields]

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 [magnetism] tag, as questions about the phenomenon & theory of magnetism do not necessarily involve the discussion of fields.

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 , as questions about the phenomenon & theory of magnetism do not necessarily involve the discussion of fields.

4684 questions
32
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10 answers

Magnetic field outside a solenoid

I couldn't picture the idea behind the zero magnetic flux outside the solenoid properly. My teacher explained it as "Components of the magnetic field in other directions are cancelled by opposing fields from neighbouring coils. Outside the solenoid…
Four Seasons
  • 2,547
20
votes
3 answers

Why iron filings sprinkled near a bar magnet aggregate into separated chunks?

When iron filings are sprinkled near a bar magnet, they reveal the "shape" of the magnetic field. (source) But why do the (needle-shaped?) filings aggregate into chunks with empty space between them rather than simply rotating in place to align with…
Sparkler
  • 3,184
10
votes
3 answers

If a compass is placed near the middle of the magnet, where will the compass needle point?

If we're thinking about a case where bar magnet is placed on a flat surface, with its N-pole on the right and a compass is placed just above the middle of the magnet, in which direction will the compass needle point? Will it go in circles? Here's a…
frankio10
  • 117
10
votes
3 answers

What is the most efficient shape of magnet?

If you had a fixed volume (x millimetres cubed) of neodymium magnet 'material' of the equivalent strength of magnetism, what shape would produce the strongest poles? Cube? Disc? Long cylinder? Or is the strength more to do with how the magnet is…
Stacker
  • 101
8
votes
3 answers

Why is my restaurant silverware magnetized?

Why is my restaurant silverware magnetized? Specifically, if I lay all three flat on the table, and touch the bottoms of the handles together, I can pull the knife with the handle of the spoon. I have a video (if I can figure out how to upload it…
Cory Kendall
  • 533
7
votes
3 answers

Does a changing magnetic field impart a force on a stationary charged particle?

Does a collapsing and re-establishing magnetic field impart a force on a stationary charged particle? Does the charge particle get repelled and or attracted? Does it move or spin?
StarDrop9
  • 1,211
6
votes
4 answers

How to determine the direction of induced current flow?

There are three ways of inducing current in a loop/coil of wire as shown in my book. We can have a magnet approach a coil of wire, or a wire approaching a magnet. Both can be understood in the same way. On the other hand, we can also change the…
most venerable sir
  • 1,331
5
votes
1 answer

Magnetic field when moving into the influence of a ferrous object

Suppose I have a magnetometer. I am on the Earth's surface, away from the influence of other magnetic sources. Assuming the magnetometer is aligned with the reference frame, it should read only the Earth's magnetic field vector at that…
Damien
  • 191
5
votes
2 answers

Magnetic Induction at the centre of a Toroid

This problem is in reference to Q3.239 in Problems in General Physics by I.E. Irodov. Question: N = $2.5*10^3 $wire turns are uniformly wound on a wooden toroidal core of very small cross-section. A current I flows through the wire. Find the ratio…
CodeBlooded
  • 163
5
votes
5 answers

Questions regarding magnetic fields and magnetic field lines

I went through certain statements regarding magnetic fields and M.G lines which I am not able to understand. First doubt: Why do magnetic field lines form closed curves? I went through some answers over the internet and on Phys. SE, but I could…
codetalker
  • 972
4
votes
4 answers

Would a vibrating bar magnet produce an oscillation in the magnetic field?

An oscillating electric charge produces an oscillating electromagnetic wave. What if I were to shake a bar magnet violently ? Would it also produce an oscillating electromagnetic wave or does this just change the magnetic field ?
user6760
  • 12,980
4
votes
2 answers

Would a magnet be able to attract an object through a sheet of stainless steel?

For example, if there were a neodymium magnet at position x=0, a sheet of stainless steel at position x=1, and a magnetic object at x=5, would the magnet still attract the object? Is the attraction force less than if the stainless steel sheet were…
user189494
4
votes
2 answers

The direction of magnetic field- right hand rule

My question is, why is the magnetic force going the same way as the fingers, why not the other way. What causes the magnetic field to choose a direction if everything is symetrical
semir213
  • 41
4
votes
1 answer

Do metal shavings affect the magnetic field they are used to visualize?

It's obvious that the use of metal shavings to visualize magnetic field lines was instrumental in Faraday's work to develop electromagnetic theory. But they also did too good a job of convincing people that magnetic lines were real. It is still one…
Yuriy S
  • 533
4
votes
1 answer

Does a magnet become less of a magnet if used to magnetize another piece of metal

If you run a magnet a few times over an unmagnetized piece of a magnetic material (such as an iron nail), you can convert it into a magnet as well. Will using a permanent magnet to magnetize something reduce the field strength of the original…
Gerard Pineau
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