Magnetic Definition and 1000 Threads

Magnetism is a class of physical attributes that are mediated by magnetic fields. Electric currents and the magnetic moments of elementary particles give rise to a magnetic field, which acts on other currents and magnetic moments. Magnetism is one aspect of the combined phenomenon of electromagnetism. The most familiar effects occur in ferromagnetic materials, which are strongly attracted by magnetic fields and can be magnetized to become permanent magnets, producing magnetic fields themselves. Demagnetizing a magnet is also possible. Only a few substances are ferromagnetic; the most common ones are iron, cobalt and nickel and their alloys. The rare-earth metals neodymium and samarium are less common examples. The prefix ferro- refers to iron, because permanent magnetism was first observed in lodestone, a form of natural iron ore called magnetite, Fe3O4.
All substances exhibit some type of magnetism. Magnetic materials are classified according to their bulk susceptibility. Ferromagnetism is responsible for most of the effects of magnetism encountered in everyday life, but there are actually several types of magnetism. Paramagnetic substances, such as aluminum and oxygen, are weakly attracted to an applied magnetic field; diamagnetic substances, such as copper and carbon, are weakly repelled; while antiferromagnetic materials, such as chromium and spin glasses, have a more complex relationship with a magnetic field. The force of a magnet on paramagnetic, diamagnetic, and antiferromagnetic materials is usually too weak to be felt and can be detected only by laboratory instruments, so in everyday life, these substances are often described as non-magnetic.
The magnetic state (or magnetic phase) of a material depends on temperature, pressure, and the applied magnetic field. A material may exhibit more than one form of magnetism as these variables change.
The strength of a magnetic field almost always decreases with distance, though the exact mathematical relationship between strength and distance varies. Different configurations of magnetic moments and electric currents can result in complicated magnetic fields.
Only magnetic dipoles have been observed, although some theories predict the existence of magnetic monopoles.

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  1. T

    Perturbation of a Magnetic Field

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  2. S

    Charged particle motion in a magnetic feild

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  3. J

    Bent rod rotating in a magnetic field

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  4. A

    I Super strong magnetic field's effect on radioactivity

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  5. A

    Understanding the Relationship Between Magnetic Field Lines and Force

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  6. S

    Maximum electric field from magnetic field

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  7. Tomi Kolawole

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  8. Alettix

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  9. S

    When Can We Use the Right Hand Rule to Find Magnetic Field Direction?

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  10. Suyash Singh

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  11. M

    Determining the direction of magnetic force

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  12. F

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  13. P

    How to measure a magnetic field

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  14. K

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  15. N

    How to calculate magnetic flux from voltage?

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  16. Ignitia

    Motion of a Charged Particle in Magnetic Field

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  17. L

    AC magnetic field and how an electric motor works....

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  18. WeiShan Ng

    Direction of the magnetic field around a solenoid

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  19. carllacan

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  20. Juan Andrew

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  21. Juan Andrew

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  22. A

    Is there a magnetic field in a capacitor during leakage or discharge?

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  23. W

    Motor: stator and rotor magnetic strength

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  24. M

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  25. Ignitia

    Magnetic Force with Parallel currents

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  26. B

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  27. Ignitia

    Biot-Savart Law For Calculating Net Magnetic Field

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  28. J

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  29. S

    Electric Field induced by a Magnetic Field inside a Solenoid

  30. H

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  31. C

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  32. R

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  33. A

    How does a magnet's magnetic field work?

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  34. R

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  35. M

    I Resistance and magnetic field effects for p-doped Ge

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  36. Muthumanimaran

    Charged pendulum in magnetic field

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  37. Harsha Avinash Tanti

    I The Role of magnetic field during the formation of small to medium scale stars

    Hi, I would like to raise a question about Role of magnetic field while formation of small to medium scale stars emerging from nebula ?
  38. A

    What is the Magnetic Flux of a White Dwarf Derived from the Sun?

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  39. G

    The Relationship between Magnets and Magnetic Forces

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  40. W

    I Northern lights and the magnetic field

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  41. N

    Magnetic field strength at a distance

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  42. Conductivity

    Derivation of magnetic field of a Solenoid: Biot savart law

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  43. TheBigDig

    Find the time dependent magnetic field intensity

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  44. S

    Modeling of two-phase flows in electric and magnetic fields

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  45. E

    What happens to the angle between two wires when one current is doubled?

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  46. E

    The work of the magnetic force

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  47. Cardinalmont

    Flux in a Uniform Magnetic Field

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  48. AdrianHudson

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  49. Physics345

    How Does a Magnetic Field Affect a Wire Carrying Current?

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  50. Y

    Induced Magnetic Field: Ferromagnetic Moment & Detection

    Does a ferromagnetic body moving through an external constant magnetic field obtain an induced magnetic moment? If so, can this induced field be detected? Which equation describes it? Thanks!
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