Two large spherical objects of mass $M$ each (uniformly distributed) are fixed as shown in figure. A small point mass $m$ is projected from point $\mathrm{A}$ heading towards center ${\mathrm{C}}_2$ of second sphere. The minimum velocity of point mass so that it can reach upto second object at point $\mathrm{B}$ is $\frac{n}{3}\sqrt{\frac{GM}{5R}}$. Then calculate $n$. [Neglect other gravitational forces]