Physics
posted by NHS .
Three uniform spheres are located at the corners of an equilateral triangle. Each side of the triangle has a length of 1.60 m. Two of the spheres have a mass of 2.20 kg each. The third sphere (mass unknown) is released from rest. Considering only the gravitational forces that the spheres exert on each other, what is the magnitude of the initial acceleration of the third sphere?

Notice a= F/m, which means that since F is dependent on mM, the acceleration is dependent now only on the masses in the other corners. It is of course a vector, so draw the system, and make the direction adjustments. The angle of the acceleration will bisect the equalateral triangle.