A magnetic field can be made by passing an electric current through a wire, and electromagnets are used for creating plenty of appliances ranging from motors, speakers, heads for tape drives, and hard disks. It is a kind of magnet in which an electrical current makes the magnetic field.
The magnetic field disperses when the current is turned off. Electromagnets usually consist of wire around a coil. A current through the wire makes a magnetic field which is concentrated in the hollow in the middle of the coil. The wire turns are often coiled around a magnetic core concentrates the magnetic flux, and it makes a more powerful magnet.
An electromagnet needs a sustained supply of current to sustain the magnetic field. Electromagnets are also employed in the industry for picking and moving heavy iron objects. This can include scrap iron steel.