Assertion: Electromagnets are made of soft iron.
Reason: Coercivity of soft iron is small.

Options

A. If both the assertion and reason are true and reason is the correct explanation of the assertion.
B. If both the assertion and reason are true but the reason is not the correct explanation of assertion.
C. If the assertion is true is true but reason is false.
D. If the assertion and reason both are false.

Answer

A

Explanation

Electromagnets are magnets, which can be turned on and off by switching the current on and off. As the material in electromagnets is subjected to cyclic change (magnification and demagnetisation), the hysteresis loss of the material must be small. The material should attain high value of I and B with low value of magnetising field intensity H. As soft iron has small coercivity, so it is a best choice for this purpose.