Two 10 kg spheres are placed 500mm apart. Express the gravitational attraction acting on one of the spheres as a percentage to its weight on earth.
for the two spheres,
F = G*10^2/0.5^2 = 400G
weight on earth is
F = gm 10g = 98.1
so now look up G, and calculate
400G/98.1 = _____ * 100%