Question

The source of all magnetic fields is:

- moving charges
- the earth's gravity
- the aurora borealis
- solar fields

Answer 1

Moving charges

Step-by-step explanation:

The source of all magnetic fields is moving electric charge: whether it is current in a wire, unpaired electrons in an atomic orbital, convection currents in the earth's liquid nickle /iron core, plasma in the sun, etc. moving electric charge is the source of all magnetic fields.