Electromagnets

An electromagnet is a soft iron core in a current carrying solenoid. The magnetic field of the coil induces magnetism in the soft iron which produces a powerful magnet with a strong magnetic field.

An electromagnet can be made by winding coils of wire on a soft iron in opposite directions round the two arms S and T of u shape soft iron bar.

When current flows round the solenoid, a strong magnetic field is produced.

The strength of an electromagnet depends on 

1. The size of the current 
2. Increase in number of turns of wire in the coil 
3. A high permeabilityPermeability is a measure of the ability of a porous material (having small spaces or holes through which liquid or air may pass) to allow fluids to pass through it. More core

Uses of Electromagnet

1. The magnetic field produced are used in electric motors and generators
2. They are used in lifting heavy materials instead of cranes 
3. They are used in electric bells, telephone earpiece
4. They are used in separating magnetic substances from non-magnetic substances
5. They are used in hospitals to remove splinter of iron or steel  from the eye