3rd of September, 2008
where $A$ and $b$ are constants, and $\overrightarrow{r}$ is the position vector.
The little green mining engineer was assigned the task to find the force necessary to keep the two halves of the planetoid apart. Help him with the calculations!
(Hint: The equations of the gravitational field are analogous to electrostatics. This problem is equivalent to finding the force needed to keep the two halves of a uniformly charged solid sphere from separating.)