5 ms·

Wow, didn't know magnetism also varies with temperature. Any simple explanation why?

• kcorbitt 13y ago
  From what I remember of my rusty high school chemistry magnetism requires a certain relatively stable configuration of the valence electrons. I'm guessing that as temperature increases it's impossible for the atoms (or even just the electrons) to maintain that configuration because of the increased energy. The electrons might even get excited enough to jump to entirely different orbitals, but I'm not sure if it works that way.
  • shardling 13y ago
    In general, magnetism requires the material to be ordered, and heating an object up involves adding lots of random motion to the system. > The electrons might even get excited enough to jump to entirely different orbitals That's what causes hot objects to glow, basically -- the electrons get pushed to higher orbitals, and then fall back down again, emitting light.
• ealloc 13y ago
  This explains it: https://en.wikipedia.org/wiki/Curie_temperature https://en.wikipedia.org/wiki/Curie_temperature In the ferromagnetic phase, the atoms are magnetically aligned and their magnetic fields adds up. If you increase the temperature past a certain point though, the atoms are jiggled enough that they can no longer stay aligned and they 'point' in random directions, and their magnetic fields cancel out. This is a big problem in hard drives: If you increase the temerature of a hard drive the magnetic regions no longer maintain their magnetization and your data gets erased. A lot of hard drive technology (eg 'perpedicular recording') has been developed to solve this problem.