Block and tackle respectively) whereas the Luff tackle and Gyn tackle have mis-matched blocks with differing numbers of pulleys. A block and tackle is characterized by the use of a single continuous rope to transmit a tension force around one or more pulleys to lift or move a load. Its mechanical advantage is the number of parts of the rope that act on the load. The mechanical advantage of a tackle dictates how much easier it is to haul or lift the load. If frictional losses are neglected, the mechanical advantage of a block and tackle is equal to the number of parts
Dump tackle Dump tackle The dump tackle is a tackling technique favoured mainly by rugby league players. The tackler wraps his arms around the ball carrier's thighs and lifts him a short distance in the air before forcibly driving him to the ground. The tackler must go to ground with the ball carrier for the tackle to be legal. In 2005 the IRB ruled that "the act of lifting an opponent off his feet in a tackle AND dropping or 'spearing' that player so that his head and/or upper body comes into contact with the ground first, is a dangerous tackle." therefore