Question

The figure gives experimentally measured B vs. H variation in a ferromagnetic material. The retentivity, co-ercivity and saturation, respectively, of the material are :

Answer 1

Correct option is D. $$1.0 T, 50 A/m$$ and $$1.5 T$$
The retentivity measures the induced magnetic field at which applied field is zero.

So, Retentivity $$= OA = 1.0T$$

Co-ercivity is the resistance of a ferromagnetic material to become demagnetized $$= OC = 50 A/m$$.

$$\therefore $$ Co-ercivity $$= 50 A/m$$

At saturation magnetization; graph becomes horizontal

So, saturation magnetization $$= M_s = 1.5 T$$

option (D) is correct.