Question

36 .​What is an electromagnet?
(i) What are the uses of electromagnet?
(ii) What are the advantages of electromagnet over permanent magnet.

Answer 1

1) An electromagnet is a temporary magnet produced by current flowing through a solenoid with soft iron core. The magnetic field remains only when the current is flowing, in absence of current it has no magnetic effect.

2) Uses of electromagnet :

Telephones
Doorbells
Stereo speakers
Car horns
Motors of domestic appliance such as washing machines.
Used in separating magnetic material from the mixture of different materials etc.

3) a) Their strength can be increased or decreased as per our requirement.
b) They can be switched on and off when required.
c) They can provide the required field due to small size.