His mathematical
theory of curved surface
laid the foundation for the
later work of Riemann For instance for the configuration Q3 for which Q is along the
perpendicular bisector of the dipole P, the magnetic moment of Q is
parallel to the magnetic field at the position 3 Hence Q3 is stable Thus,
(a) PQ1 and PQ2
(b) (i) PQ3, PQ6 (stable); (ii) PQ5, PQ4 (unstable)
(c) PQ6
5