In Zangwill's Modern Electrodynamics the magnetic torque is derived in Eq. 12.63 to be
\begin{equation} \mathbf{N}(\mathbf{r}_0) = \mathbf{m} \times \mathbf{B}(\mathbf{r}_0) + \mathbf{r}_0 \times \mathbf{F}(\mathbf{r}_0) \end{equation}
where the force $\mathbf{F}$ is previously derived (Eq. 12.39) as
\begin{equation} \mathbf{F}(\mathbf{r}) = m_{k} \nabla B_{k} \end{equation}
which is the magnetic displacement force.
As stated in Zangwill, if $\mathbf{r}_0$ is at the origin, then the second term $\mathbf{r}_0 \times \mathbf{F}(\mathbf{r}_0)$ obviously goes to zero, but what if it is the case that $\mathbf{r}_0$ is not at the origin, what is the physical interpretation of the additional torque $\mathbf{r}_0 \times \mathbf{F}(\mathbf{r}_0)$? Is this like the gravity gradient torque on a satellite?
