Magnets have two poles - North and South No monopoles - dipole effect.
"Like poles repel, unlike attract"
Close loops
Don't cross
Direction going North to South!!!
Usually, there's the greatest density of field lines at the pole, i.e. next to the magnet's N or S.
Ferromagnetism - Fe, Co, Ni
Electron spins (moving charge) in atoms are aligned to give an overall magnetic effect. Small sections (Domains) have many atoms with their electron spins all aligned such that they produce an overall magnetic field.
In usual ferromagnetic materials, the domains are unaligned, so they don't have an overall magnetic field (domains cancel each other out)
Once a ferromagnetic material has its domains all aligned, it becomes a temporary magnet.
Hence, if you heat up a ferromagnetic material, apply a magnetic field to align the domains, and then cool it, you get a permanent magnet, as the domains become fixed.
Magnetic fields are associated with currents.
