The surprising dynamics of a chain on a pulley: lift off and snapping

摘要: The motion of weights attached to a chain or string moving on frictionless pulley is classic problem introductory physics used understand the relationship between force and acceleration. Here, we consider dynamics when one removed and, thus, end pulled with constant This simple change has dramatic consequences for ensuing motion: at finite time, 'lifts off' from free subsequently accelerates faster than that pulled. Eventually, undergoes reversal curvature reminiscent crack, snap, whip. We combine experiments, numerical simulations, theoretical arguments explain key aspects this dynamical problem.