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

The relative permeability of iron is $2000$. Its absolute permeability in $SI$ units will be (given $\frac{\mu_0}{4 \pi} = 10^{-7} \text{ SI units}$):

The magnetic susceptibility of iron is $5499$. The relative permeability of iron will be

At a temperature of $30\,^oC$,the susceptibility of a ferromagnetic material is found to be $\chi$. Its susceptibility at $333\,^oC$ is....$\chi$.

An iron rod is placed parallel to a magnetic field of intensity $2000 \text{ A/m}$. The magnetic flux through the rod is $6 \times 10^{-4} \text{ Wb}$ and its cross-sectional area is $3 \text{ cm}^2$. The magnetic permeability of the rod in $\text{Wb/(A} \cdot \text{m)}$ is:

The susceptibility of $Al$ is $2 \times 10^{-5}$. The percent increase in the magnetic field when the space within a current-carrying toroid is filled with $Al$ is: