Magnetic field intensity is defined as the degree to which the magnetising field can magnetise a material. The magnetic field which magnetises a material placed in it is known as the magnetising field. Magnetic field intensity is denoted by ‘H‘ and also known as intensity of magnetising field or magnetising force.
Magnetic field intensity (H) is equal to the ratio of the magnetic flux density (B) to the permeability of the material. The SI unit of magnetic field intensity is Am-1.
where
μo is known as absolute permeability of vacuum or free space and μo = 4π x 10-7 TmA-1
μr is the relative permeability
B is the magnetic flux density