Constant magnets

A magnet is an object made of a special substance that produces a magnetic field.
Each magnet has at least one north and one south pole.
Scientists agreed to hold that magnetic fields begin from the north pole and end in the south pole.
Nowadays, magnets are made of ferrites, so-called alnico (aluminium-nickel-cobalt alloy) and neodymium-boron-iron alloy.
Today ...