Question

The drawing shows three particles far away from any other objects and located on a straight line. The masses of these particles are mA = 363 kg, mB = 517 kg, and mC = 154 kg. Find the magnitude and direction of the net gravitational force acting on each of the three particles (let the direction to the right be positive).

Answer 1

There is not enough information here. You need to be given or have enough information to find rAB, rBC, rAC, where rAB is the distance between mass A and mass B, etc.

The magnitude of the force acting on mass A is

-G*mA*mB/rAB^2 - G*mA*mC/rAC^2

apply this same model to find the force acting on mass B and mass C