Mechanical advantage force applied at "A" the end of the rope, and let "F" be the force at "B" on the moving block. Like the velocities "F" is directed downwards and "F" is directed upwards. For an ideal block and tackle system there is no friction in the pulleys and no deflection or wear in the rope, which means the power input by the applied force "F""V" must equal the power out acting on the load "F""V", that is The ratio of the output force to the input force is the mechanical advantage of an ideal gun tackle system, This analysis generalizes
Grappling hook Grappling hook A grappling hook or grapnel is a device with multiple hooks (known as "claws" or "flukes"), attached to a rope; it is thrown, dropped, sunk, projected, or fastened directly by hand to where at least one hook may catch and hold. Generally, grappling hooks are used to temporarily secure one end of a rope. They may also be used to dredge for submerged objects. Historically, grappling hooks were used in naval warfare to catch ship rigging so that it could be boarded. A common design has a central shaft with a hole ("eye") at the shaft base to