Magnetism Summary

Key Concepts

  • Magnetic Domain: A group of atoms with aligned N-poles.
  • Magnet Poles: Magnets have both N-pole and S-pole. Like poles repel; unlike poles attract.
  • Magnetic Materials: Attracted to magnets and other magnetic materials.
  • Magnetic Field: Region around a magnet where it attracts opposite poles. Field lines go from N-pole to S-pole.
  • Magnetic Shielding: Making a space free from magnetic fields.
  • Induced Magnetism: Magnetizing a material with an external magnetic field.
  • Temporary Magnets: Magnets that behave like a magnet only in the presence of current.
  • Permanent Magnets: Magnets that retain their magnetic properties without current.
  • Diamagnetic Materials: Materials with zero net magnetic fields per atom.
  • Paramagnetic Materials: Materials with a small net magnetic field per atom.
  • Ferromagnetic Materials: Materials with a large net magnetic field per atom.
  • Earth's Magnetic Field: Resembles a bar magnet's field, protecting life from cosmic rays and solar radiation. Earth's geographic and magnetic poles differ by 11.3 degrees, and migratory animals use Earth's magnetic field for navigation.