Question:

A domain in ferromagnetic iron is in the form of a cube of side length 1 μm . 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 55g/mole and is density is 7.9 g / cm³ . Assume that each iron atom has a dipole moment of 9.27 ×10⁻²⁴ Am².