A particle of mass 3m is located 1.00 m from a particle of mass m.
(a) Where should you put a thin mass M 80 that the net gravitational force on M due to the two masses is exactly zero?
(b) Is the equilibrium of M at this point stable or unstable (i) for points along the line connecting m and 3m, and (ii) for points along the line passing through M and perpendicular to the line connecting m and 3m?