Backgammon according to the normal movement rules. The first player to bear off all fifteen of his/her own checkers wins the game. If the opponent has not yet borne off any checkers when the game ends, the winner scores a "gammon", which counts for double stakes. If the opponent has not yet borne off any checkers and has some on the bar or in the winner's home board, the winner scores a "backgammon", which counts for triple stakes. To speed up match play and to provide an added dimension for strategy, a doubling cube is usually used. The doubling cube is
Ridge push Ridge push Ridge push or sliding plate force is a proposed driving force for plate motion in plate tectonics that occurs at mid-ocean ridges as the result of the rigid lithosphere sliding down the hot, raised asthenosphere below mid-ocean ridges. Although it is called ridge push, the term is somewhat misleading; it is actually a body force that acts throughout an ocean plate, not just at the ridge, as a result of gravitational pull. The name comes from earlier models of plate tectonics in which ridge push was primarily ascribed to upwelling magma at mid-ocean ridges pushing or wedging the