Three uniform spheres each having a mass ‘M’, and radius ‘a’ are kept in such a way that each touches the other two. Find the magnitude of gravitational force on any of spheres due to the other two.

Force of attraction between two masses=GM mr2 Force on any sphere is  F=GM24a2;universal gravitation constant=G; mass=m; distance between two centres of spheres=r=2a;  The resultant force on any sphere is     from parallelogram law of addition of vecotors F1=F12+F22+2F1F2cos600  here F1=F2=F F1=3F F1=3GM4a2=force on each sphere