Law of Acceleration

Remember that Newton's first law stated that an object with no net force acting on it will not accelerate. Newton's second law of motion, though, states that an unbalanced force (one that is not equally opposed by another force) acting on an object will cause the object to accelerate. The object's mass, which measures its inertia, also determines how much the object's movement will change. From this, Newton derived the formula a= F/m, where acceleration is directly proportional to force and inversely proportional to object mass.