Define magnetisation $(M)$ and give its unit and dimension.

The magnetic susceptibility of a paramagnetic substance at $-123^{\circ} C$ is $0.0060$. What will be its value at $-173^{\circ} C$?

The unit for molar susceptibility is

$A$ solenoid having $400$ turns per metre has a core of a material with relative permeability $400$. When a current of $0.5 \ A$ is passed through it,the magnetization of the core material in $Am^{-1}$ is nearly

$A$ material of $0.25 \ cm^2$ cross-sectional area is placed in a magnetic field of strength $(H) 1000 \ Am^{-1}$. Then,the magnetic flux produced is (Susceptibility of material is $313$) (Permeability of free space,$\mu_0 = 4 \pi \times 10^{-7} \ Hm^{-1}$)

$ \chi_{1} $ and $ \chi_{2} $ are the magnetic susceptibilities of a paramagnetic material at temperatures $ T_{1} \ K $ and $ T_{2} \ K $ respectively. Then: