In the case of a pair of monopoles being used (i.e. electric dipole model), the force is F dipole = ( m ⋅ ⋅ ∇ ∇ ) B . And one can be put in terms of the other via the relation F loop = F dipole + m × × ( ∇ ∇ × × B ) − − ( ∇ ∇ ⋅ ⋅ B ) m .