Two identical solid spheres, each of mass 10kg, are fixed at two diagonally opposite corners of a square of side 0.20m. A small test mass of 5.0kg is placed at a third corner of the square.
(a) Draw a labelled sketch showing all gravitational forces acting on the 5.0kg mass.
(b) Calculate the magnitude of the gravitational force exerted on the test mass by each sphere separately.
(c) Using vector addition, find the magnitude and direction of the net gravitational force on the test mass. Express the direction as an angle measured from one side of the square.
(d) Comment on how the net force would change, if at all, if the masses of the two fixed spheres were unequal.