INVENTIONS
Speakers
the electromagnet and the speaker cone can be made to back and forth. If the variation of the electric current is at the same frequencies of sound waves, the resulting vibration of the speaker cone will create sound waves, including that from voice and music.
Relay Switches
The basic functioning of an electromagnetic relay involves generating a magnetic field in an iron core by the passage of an electric current through a coil of wire wound around it. When an electric current passes through the coil, the magnetic field generated makes or breaks of circuit.
Trains
A maglev train works without wheels and is propelled by electromagnetic forces. For transportation
Electromagnetic Locks
when electric current passes through the coil, the core becomes an electromagnet. It attracts a metal plate on the same side of the door.
Electric motors
In all electric motors, a current traveling through a wire is acted upon by a magnetic field at right angles to he magnetic field creates a force that rotates the coil of wire.