$A$ toroid has an average diameter of $2.5\,m$,$400$ turns,and a current of $2\,A$. If the total magnetic field inside the toroid is $10\,T$,what is the intensity of magnetization (in $A/m$)?

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:

When a piece of a ferromagnetic substance is placed in a uniform magnetic field,the flux density inside it is four times the flux density away from the piece. The magnetic permeability of the material is

By putting a magnetic substance of volume $30\, cm^3$ in a magnetising field of strength $\frac{1250}{\pi} \, A/m$,the value of the produced magnetic moment is $6\, A\cdot m^2$. Calculate the value of magnetic induction produced in the substance in $T$.

$A$ substance has a mass of $1 \, g$ and a density of $5 \, g/cm^3$. Its magnetic dipole moment is $6 \times 10^{-7} \, A \cdot m^2$. What is the magnetization in $A/m$?

$A$ domain in ferromagnetic iron is in the form of a cube of side length $1\; \mu m$. Estimate the number of iron atoms in the domain and the maximum possible dipole moment and magnetisation of the domain. The molecular mass of iron is $55\; g/mol$ and its density is $7.9\; g/cm^3$. Assume that each iron atom has a dipole moment of $9.27 \times 10^{-24}\; A m^2$.