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Iron nails in above figure acts as magnet with its two ends acting as North and South
Pole.

 Electromagnet behaves as a magnet as long as current flows through the wire.
 If a magnet loses its magnetism is called as Temporary magnet.

 Magnet that retains its magnetic strength for longer period of time is called Permanent magnet.
 SOLENOID: A solenoid is a device in which a long insulated wire is wound around a hollow
metallic core. It is cylindrical in shape and can be used as an electromagnet.

 Factors affecting strength of electromagnet are:
 The number of turns in the coil
 The amount of current flowing through the circuit
 Nature of the material used as core.