Let us suppose that there is a constant uniform magnetic field perpendicular to a surface of a block of iron. Why does the magnetic field increases inside the block? Is it due to the alignment of the small magnetic dipoles in the direction of magnetic field?If this is so is it analogous to the field developed inside when a electric field is applied. In the case of electric field the field inside reduces by $\varepsilon_r$ times. Is it true in case of magnetic field? Will the magnetic field be increased by $\mu_r$ times?

Let us suppose that there is a constant uniform magnetic field perpendicular to the surface of a block of iron. Why does the magnetic field increases inside the block? Is it due to the alignment of the small magnetic dipoles in the direction of magnetic field? If this is so, is it analogous to the field developed inside when a electric field is applied to a dielectric material? In the case of electric field, the field inside reduces by $\varepsilon_r$ times (where $\varepsilon_r$ denotes the relative permittivity of the dielectric material), Is it equally true in the case of magnetic field? Will the magnetic field increase by $\mu_r$ times? (where $\mu_r$ denotes the relative permeability of the material)