Question

For different substances, hysteresis $(B-H)$ curves are given as shown in figure. For making an electromagnet, which of the following is most suitable?

• A. Only $C$
• B. Both $B$ and $C$
• C. Both $A$ and $B$
• D. Only $B$

Answer 1

The correct option is D Only $B$

For making electromagnet, we need a material which has smaller magnitude of retentivity as well as coercivity.

The graph shown in option $B$ satisfies both the requirements.

Hence, $\left(B\right)$ is the correct answer.

Why this Question? Note: The materials having lower value of retentivity as well as corecivity is best suited to make an electromagnet.