Magnetic hysteresis is exhibited by . . . . . . magnetic materials.

If the given figure shows the relation between magnetic field ($B$ - along $y$-axis) and magnetic intensity ($H$ - along $x$-axis) of a ferromagnetic material,then the point that represents the coercivity of the material is

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?

$A$ ferromagnetic material of volume $10^{-3} \, m^3$ is subjected to a magnetic field with a frequency of $50 \, Hz$. The area of the hysteresis loop is $0.1 \, M.K.S. \, \text{units}$. Calculate the energy dissipated in $1 \, \text{sec}$.

Which of the following statements is incorrect about hysteresis?

The coercivity of a small magnet is $4 \times 10^3 \ A/m$. It is placed inside a solenoid of length $1 \ m$ having $500$ turns to demagnetize it. The current that must be passed through the solenoid is .......... $A$.