rotating mechanism
51Inventions in medieval Islam — A significant number of inventions were developed in the medieval Islamic world, a geopolitical region that has at various times extended from Al Andalus and Africa in the west to the Indian subcontinent and Malay Archipelago in the east.… …
52Mechanical watch — The movement of a Russian watch A mechanical watch is a watch that uses a mechanical mechanism to measure the passage of time, as opposed to modern quartz watches which function electronically. It is driven by a spring (called a mainspring) which …
53IBM Selectric typewriter — The IBM Selectric typewriter (occasionally known as the IBM Golfball typewriter) is an influential electric typewriter design. It was introduced in 1961.Instead of a basket of pivoting typebars the Selectric had a pivoting type element… …
54Gravitomagnetism — (sometimes Gravitoelectromagnetism, abbreviated GEM), refers to a set of formal analogies between Maxwell s field equations and an approximation to the Einstein field equations for general relativity, valid under certain conditions. For instance …
55Rangekeeper — Rangekeepers were electromechanical fire control computers used primarily during the early part of the 20th century. They were sophisticated analog computers whose development reached its zenith following World War II, specifically the Computer… …
56Gear — For the gear like device used to drive a roller chain, see Sprocket. This article is about mechanical gears. For other uses, see Gear (disambiguation). Two meshing gears transmitting rotational motion. Note that the smaller gear is rotating… …
57Black hole — For other uses, see Black hole (disambiguation). Simulated view of a black hole (center) in front of the Large Magellanic Cloud. Note the gravitat …
58Oxidative phosphorylation — The electron transport chain in the mitochondrion is the site of oxidative phosphorylation in eukaryotes. The NADH and succinate generated in the citric acid cycle are oxidized, releasing energy to power the ATP synthase. Oxidative… …
59Watch — For other uses, see Watch (disambiguation). Early wrist watch by Waltham, worn by soldiers in World War I (Deutsches Uhrenmuseum, Inv. 47 3352) A watch is a small timepiece, typically worn either on the wrist or attached on a chain and carried in …
60Wheellock — Wheellock, wheel lock or wheel lock, is a mechanism for firing a firearm. It was the next major development in firearms technology after the matchlock and the first self igniting firearm. The mechanism is so called because it uses a rotating… …
