Coercivity is defined as the value of the magnetising field at which the intensity of magnetisation becomes zero. It is also known as coercive field.
The magnetism remaining in the magnetic material, even when the magnetising field is reduced to zero is called residual magnetism. The power of retaining this
Soft magnetic materials have low retentivity and low coercivity. These are those materials which have high initial permeability, low hysterisis loss and large magnetic induction.