 In 1820 Danish science Hans Christian Oersted accidentally discovered that electric current produces a magnetic field.  He set up compasses around a wire. With no current all needles pointed north. When current was flowing, all needles pointed in different directions!

 The relationship between electricity and magnetism is called ELECTROMAGNETISM

 The magnetic fields produced by a current has both strength and direction. The field can be turned on or off, have its direction changed, or strength changed.

 1. Increase the amount of current in the wire.  2. Make a loop with the wire. (This causes the magnetic field lines to bunch inside the wire – increasing the field)

 Both solenoids and electromagnets use electric current and coiled wires to produce strong magnetic fields.

SOLENOIDS - A coil of wire with a current. - Makes similar to a north and south pole of a magnet. - Can change poles by changing direction of current. ELECTROMAGNETS - A solenoid with an ferromagnetic core. - Current in wire and magnetized core create electric current. - Overall magnetic field is much greater.

 When a wire with a current is placed in a magnetic field, electrical energy is transformed into mechanical energy.

 The rotation of a wire loop in a magnetic field is the basis for galvanometers which detect small electric currents.  The electric current, turns the pointer of a galvanometer

 Electric motors transform electrical energy into mechanical energy.

 An electric current is induced in a conductor when the conductor moves through a magnetic field.  This is called electromagnetic induction.