So far three forces that differ fundamentally have been identified in nature between if for its origins and magnitude. I hope that ye teachers and students of the causes fall more than three. 1) Gravitational force, 2) the electromagnetic force, 3) and nuclear forces. We consider the motion of a body falling freely. The direction of motion coincides with the direction of the field. As the intensity of the field it is given by the expression. G = F / M, F = MG. And in such conditions, the body falls under the action of a constant force, implying that its motion is uniformly accelerated.
When the body is thrown vertically upward, acts on the force exerted by the gravitational field that gives it an acceleration in the opposite direction to their movement and as a consequence, body ascent rate decreases progressively, until cancelled. And the body is at its height maximum since the movement changes direction and the body falls. You can observe that these forces can appreciate the consequences that produces movement. No movement forces would be completely null and void, because even when the bodies are found on a surface, the force of gravity prints a motion on such bodies which tend towards the Earth. Which allows us to think that even when the force exists if not It has internal movements in it which transformed it into energy, it is impossible to determine mathematically as metaphysically. I think the rubbing of bodies on Earth occurs by sequences of magnetic movements which are attracted by the gravity of the universe and not Earth’s gravity. Because gravity is not found on Earth is in the universe, what is happening is that some planets receive more force by the universe and others receive less this depends on the distances of the universe to its center of explosion, since the universe continues continuously exploding and creating new matter.