Pulley system, the massless and frictionless pulleys do not dissipate energy and allow for a change of direction of a rope that does not stretch or wear. In this case, a force balance on a free body that includes the load, "W", and "n" supporting sections of a rope with tension "T", yields: The ratio of the load to the input tension force is the mechanical advantage "MA" of the pulley system, Thus, the mechanical advantage of the system is equal to the number of sections of rope supporting the load. A belt and pulley system is characterised by two or
Rope-a-dope power of welterweight titlist Miguel Cotto in their November 2009 fight. Pacquiao followed the rope-a-dope with a knockdown. Nicolino Locche, Argentine boxer nicknamed "El Intocable" (The Untouchable), used this technique extensively throughout his career. He would get against the ropes and dodge nearly every single punch until his opponent would tire, then he would take him down with combinations. "Irish" Micky Ward utilized this strategy during many of the fights in the later part of his career. Ward would wait for his opponent to become fatigued and would hit with either a left hook to the body or any number