For 10 points, name this phenomenon whose field has both north and south poles, and which is often paired with electricity.
Biot-Savart's Law gives the field of this type for a current carrying wire; the strength of that field is measured in Gausses and Teslas. There are para-, dia-, and ferro- forms of this phenomenon, the latter of which is expressed by metals such as nickel and iron. For 10 points, name this phenomenon whose field has both north and south poles, and which is often paired with electricity.
Biot-Savart's Law gives the field of this type for a current carrying wire; the strength of that field is measured in Gausses and Teslas.
magnetism [or magnetic field]