art blathered on and scribbled:

WHY? bECAUSE THE MAGNETIC FIELD LINES FROM A DIAMAGNETIC MATERIAL
SUCGH AS ALUMINUM OR COPPER IS AT RIGHT ANGLES TO THE AXIS OF CURRENT
FLOW WHICH IS NOT THE SAME AS WITH A FERRITE MAGNETIC MATERIAL

so, you should be able to take a compass, a piece of copper wire, and a
piece of steel or iron wire and tell the difference between the material
just by passing a dc current through them?