Abstract for: Newton’s Laws of System Dynamics
This paper proposes an understanding of system dynamics models by analogy with Newtonian mechanics. By considering the second derivative form of a model, and extending the concept of feedback loop impact, it is shown that Newton’s three laws of motion have their equivalent in system dynamics, and that the impacts of the forces on the stocks are the measure of the force that determines stock behavior. The concepts of mass, inertia, momentum, and friction are explored as to their usefulness in understanding model behavior. The Newtonian understanding is applied to two standard system dynamics models, inventory-workforce and economic long-wave, where their behavior is analyzed using force dominance on the stocks and the laws of motion. The method, and conceptual understanding, is commended for further exploration.