In the following graph of flux density $(B)$ versus magnetizing force $(H)$,coercivity and retentivity are respectively represented by the points

$A$ bar magnet has a coercivity of $4 \times 10^3 \text{ A m}^{-1}$. It is placed inside a solenoid of $12 \text{ cm}$ length and $60$ turns. The current that should be passed through the solenoid to demagnetize the bar magnet is: (in $\text{ A}$)

The $B-H$ curves $S_1$ and $S_2$ in the adjoining figure are associated with:

The intensity of magnetisation $I$ is plotted against the magnetising field $H$ for different substances. The curves $A$ and $B$ shown in the adjoining figure are associated with

Magnetic materials used for making permanent magnets $(P)$ and magnets in a transformer $(T)$ have different properties. Of the following,which property best matches the type of magnet required?

Magnetic hysteresis is exhibited by magnetic materials which are