An electromagnet is a type of magnet in which the magnetic field is produced by an electric current. The magnetic field disappears when the current is turned off.
Our electromagnet comprises of a U-shaped soft iron core of circular section, with armature and a carrying hook.
300 turns of an insulated copper wire are wound on it.
The electromagnet is provided with connectors, for use on 4-6 volts D.C.
Students can compare electromagnets and permanent magnets and appreciate that the main advantage of an electromagnet over a permanent magnet is that the magnetic field can be quickly changed in the former by controlling the amount of electric current in the winding. However, electromagnets require a continuous supply of current to maintain their magnetic fields.