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. bbbl67

    B Are magnetic fields generated through radio frequencies?

    I seem to hear about huge astronomical events that generate radio waves seem to come from objects with huge magnetic fields, such as neutron stars and black holes. Does that mean magnetic fields only come from the radio end of the spectrum, and not higher frequencies, like IR, UV, X-rays, etc?
  2. LCSphysicist

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  3. dextercioby

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  4. S

    I Magnetar Mystery: How Do Neutrons Generate a Magnetic Field?

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  5. Adgorn

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  6. P

    I Exploring Newton's Third Law in an Imaginary Magnetic Field

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  7. A

    I Derivation of the magnetic flux in coaxial cable

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  8. Hasan2022

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  9. J

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  10. J

    A curved wire rotating in and out of a magnetic field

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  11. A

    Calculating a large toroid's magnetic field

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  12. J

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  13. A

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  14. A

    Magnetic field generated by an infinitely long current-carrying wire

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  15. J

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  16. A

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  17. Sunny Singh

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  18. EmmanKR

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  19. M

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  20. L

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  21. Gbl911

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  22. Mr_Allod

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  23. I

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  24. T

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  25. L

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  26. S

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  27. V

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  28. Dom Tesilbirth

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  29. Mr_Allod

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  30. F

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  31. J

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  32. W

    B What Advantages Does a V-Shape Magnetic Accelerator Have Over a Linear One?

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  33. SanaiBongchul

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  34. Rzbs

    I What makes cobalt oxide (co3o4) a magnetic material?

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  35. Salmone

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  36. rayjbryant

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  37. S

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  38. B

    Why Do My T1 and T2 Values for Mineral Oil Show Significant Errors?

    I have found articles that show T1 and T2 values for mineral oil and I compare them to mine and there is over 50% error also I know that T1>T2 but mine numbers don't follow that scheme.
  39. H

    I Is the scalar magnetic Potential the sum of #V_{in}# and ##V_{out}##

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  40. A

    Magnetic field's effect on a charged particle's motion

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  41. Boltzman Oscillation

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  42. Woomir

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  43. S

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  44. R

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  45. B

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  46. K

    I Hamiltonian of a particle in a magnetic field

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  47. K

    I Exact dynamics of spin in varying magnetic field

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  48. K

    B Magnetic pendulum and electric energy....

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  49. Istiak

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  50. K

    I Definition of magnetic moment in quantum mechanics

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