Question

Compare electromagnet with a permanent magnet.

Answer 1

Electromagnet	Permanent Magnet
1) It is made of soft iron.	1) It is made of steel.
2) It produces the magnetic field so long as current flows in its coils.	2) It produces permanent magnetic field.
3) The magnetic field strength can be changed.	3) The magnetic field strength cannot be changed.
4) The electromagnet can be made as strong as needed.	4) The permanent magnets are not so strong.
5) The polarity of an electromagnet can be reversed.	5) The polarity of permanent magnet cannot be reversed.
6) It can be easily demagnetised by switching off the current.	6) It cannot be easily demagnetised.