* Generators convert mechanical energy into electrical energy. They work by using a magnetic field to induce an electric current in a conductor. The direction of the current is determined by the direction of the magnetic field and the direction of the motion of the conductor.
* Electromagnets create a magnetic field by passing an electric current through a coil of wire. The strength of the magnetic field is proportional to the amount of current flowing through the coil.
* Relays are switches that are operated by an electric current. They work by using a magnetic field to move a contact from one position to another.
* Magnetic recording devices store data on magnetic tape or disks. They work by using a magnetic field to write data to the tape or disk and then read it back by using a magnetic field.
