· Every magnet has two poles : north – south
· The poles exhibit forces similar to the forces between electric charges
· Magnetic poles ( monopoles ) can not be isolated
· Electric currents produce magnetic fields (Electromagnet)
· Permanent magnets have permanent magnetic fields (iron) electrons have an intrinsic magnetic field
· Thus, there are two ways of producing magnetic fields.
· An electric current can be produced in a circuit by moving a magnet near the circuit
Electric Fields Û Magnetic Fields
· The Earth is a large permanent magnet.