Question

three uniform spheres each having m and radius r are kept in such a way that each touches the other. find the magnitude of the gravitational force on any sphere due to the other two. ans.$\sqrt{3$of GM^2/4R^2

Answer 1

Force between two spheres will be $F= \large\frac{GMM}{(2R)^2}=\frac{GM^2}{4R^2}$ Two forces of equal magnitude are acting at angle $60^{\circ}$ on any of the sphere $F_{net}=\large\frac{\sqrt 3}{4} \frac{GM^2}{R^2}$ Hence a is the correct answer.