Force
A force changes the state of an object (some physical quantity changes) or, strictly, the states of two objects, since the force is an interaction. For example, a force causes an affected object to be pushed or pulled in a certain direction. This  changes the object's momentum. Forces cause objects to accelerate, add to the object's overall pressure, change direction, or change shape. Because the magnitude and direction of a force are both important, force is a vector quantity. The strength of a force is measured in newtons (N).  There are four fundamental forces in physics.