Ampere's thinking
Physics Narrative
for 11-14
An early view of the connection between electric currents and magnetism
The French scientist Andre-Marie Ampere considered that the phenomenon of magnetic fields being produced by electric currents is a fundamental feature of magnetism. In fact, he suggested that all magnetism, including that associated with permanent magnets, is due to electric currents. But how can electric currents be responsible for the behaviour of permanent magnets, when there seems to be no electric current?
Ampere's reasoning went something like this:
A permanent magnetic effect in a piece of iron or steel is due to the circulation of electric charge (imagine the motion of electrons around the nucleus of each atom). This moving charge constitutes a minute electric current and so all magnetic effects are ultimately due to electric currents.
