Newton's second law, called the law of acceleration, states that the acceleration of an object is equal to the total force acting on the object divided by its mass. Written in another way, the law says that the total force acting on an object is equal to its mass times its acceleration. By way of example, imagine that a person kicks a ball. The ball will move away from the person at a certain speed. Now imagine that the person kicks the ball twice as hard. The ball wilk move away twice as fast. Or, if a person kicks a ball against the wind, then the acceleration of the ball will depend on the force of the kick minus the force of the wind.