benEzra
Moderator Emeritus
That's not the copper being magnetized; that's the direct field created by the moving electrons themselves.In the presence of a strong magnetic field even copper becomes magnetic. It doesn't stay magnetized when the field is removed like steel will do.
I have seen bussbars carrying 1200 amps at low voltage In a copper leach plant exibit such a strong magnetic field that you could not carry a tool box past them without the tool box pulling over to the buss. It was hell on wrist watches.
Read the other thread on this subject.
Jim
Paramagnetism, diamagnetism, and ferromagnetism are properties of atoms, but you don't need atoms to create a magnetic field, just moving charged particles. Any electrical current, even one flowing through a vacuum, creates a magnetic field.