Question

What is an electromagnet? State two ways by which the strength of an electromagnet can be increased.

Answer 1

Hint: The electromagnet is made up of the material which has high permeability by banding the material in a suitable form to create a magnetic field from the electric field. The Electromagnetic coil depends on some factors. The change in that factor may lead to an increase in its strength.

Formula Used: \[{{B}_{S}}={{\mu }_{0}}ni\]

Complete step by step answer:
The term electromagnet itself states the definition of it. Here the electro means the electric part which for the current, electric field, etc. And magnet means the material to attract or distract by the materials field. So the electromagnet is the material which shows its magnetic field effect when the electric current passes through it, and that normally the material cannot show the magnetic effect. Electromagnets are made up of those materials which have high permeability.
If a coil is made up of a suitable material and the current passing through it and it shows the electromagnetic effect which shown in the figure,

The magnetic field of the coil is depending upon materials permeability, the number of turns, and current.
  \[{{B}_{S}}={{\mu }_{0}}ni\]
To increase the strength of the material,
(1) The material has high permeability and low retentively can be inserted in the coil. For example, soft iron is the core material with these properties.
(2) To increase the strength, the number of turns in the coil can be increased.
(3) The current in the coil also can be increased.

Additional Information:
Permeability: It is the quantity to measure the influence of the material’s flux.
Retentively: It is the ability of the material to remain under the effect of any field after the removal of that field.

Note: In the making of the electromagnet the material should have a suitable property for example high permeability. If the number of turns is increased then the effect of the electromagnetic field also increases due to crowdedness of it. When the passing current is stopped the electromagnetic field is removed from the electromagnet.