Acceleration is a vector quantity that is defined as the rate at which an object changes its velocity. An object is accelerating if it is changing its velocity. Acceleration has to do with changing how fast an object is moving. If an object is not changing its velocity, then the object is not accelerating. Basically the changing of speed.
Acceleration, in physics, is the rate of change of velocity of an object. An object's acceleration is the net result of any and all forces acting on the object, as described by Newton's Second Law.
