The magnetic susceptibility of any paramagnetic material changes with absolute temperature $T$ as

$A$ bar magnet having length $5 \ cm$ and area of cross-section $4 \ cm^{2}$ has a magnetic moment of $2 \ Am^{2}$. If the magnetic susceptibility is $5 \times 10^{-6}$,the magnetic intensity will be:

$A$ solenoid has a core of material with relative permeability $501$. The windings of the solenoid are insulated from the core and carry a current of $2.5 \ A$. If the number of turns is $900$ per metre,the magnetization in $A \ m^{-1}$ is:

The relation between $\mu$ and $H$ for a specimen of iron is $\mu = [\frac{0.4}{H} + 12 \times 10^{-4}] \ H m^{-1}$. The value of $H$ which produces a flux density of $1 \ T$ will be ($\mu =$ magnetic permeability,$H =$ magnetic intensity).

The percentage increase in magnetic field $(B)$ when the space within a current-carrying solenoid is filled with magnesium (magnetic susceptibility $\chi_{mg} = 1.2 \times 10^{-5}$) is:

The value of aluminium susceptibility is $2.2 \times 10^{-5}$. The percentage increase in the magnetic field if space within a current-carrying toroid is filled with aluminium is $\frac{x}{10^{4}}$. Then the value of $x$ is ...... .