Differential pulley were. Next, the downward force acting on the lower pulley equal the upward forces acting on it, so Additionally, there is no net torque or moment around the compound pulley, so the clockwise torque is equal to the anticlockwise torque: Substituting "F" and "F" from the above equations, Rearranging gives As "F" = , Finally, the mechanical advantage, = or . Differential pulley A differential pulley, also called "Weston differential pulley", sometimes "chain hoist" or colloquially "chain fall", is used to manually lift very heavy objects like car engines. It is operated by pulling upon the slack section of a
Hook (Once Upon a Time) memories. Upon recalling what Emma did to him, Hook immediately renews his plot to revive every Dark One and kill Rumplestiltskin. However, after a confrontation with Emma and Regina, Hook has a crisis of conscience and turns on the Dark Ones. Subsequently, Hook sacrifices his life to destroy the Darkness once and for all. However, upon the discovery that Gold has betrayed Hook to take back his power, Emma blackmails him into helping her get into the Underworld, so that she may launch a mission to revive him. In the Underworld, Hook is tortured by Hades. However, with the help