lever arm of internal forces
41Glossary of rail terminology — Rail transport Operations Track Maintenance High speed Gauge Stations …
42Phonograph — Turntable redirects here. For other uses, see Turntable (disambiguation). Edison cylinder phonograph ca. 1899 …
43Carburetor — Bendix Technico (Stromberg) 1 barrel downdraft carburetor model BXUV 3, with nomenclature A carburetor (American spelling), carburettor, or carburetter (Commonwealth spelling) is a device that blends air and fuel for an internal combustion engine …
44education — /ej oo kay sheuhn/, n. 1. the act or process of imparting or acquiring general knowledge, developing the powers of reasoning and judgment, and generally of preparing oneself or others intellectually for mature life. 2. the act or process of… …
45keyboard instrument — ▪ music Introduction any musical instrument on which different notes can be sounded by pressing a series of keys, push buttons, or parallel levers. In nearly all cases in Western music the keys correspond to consecutive notes in the… …
46M1918 Browning Automatic Rifle — Not to be confused with Browning BAR. Rifle, Caliber .30, Automatic, Browning, M1918 The M1918A2 BAR Type …
47Space Shuttle Challenger disaster — For more information about the final mission and crew of the Challenger, see STS 51 L. Space Shuttle Challenger s smoke plume after the in flight breakup that killed all seven crew members …
48List of Chinese inventions — A bronze Chinese crossbow mechanism with a buttplate (the wooden components have …
49police — /peuh lees /, n., v., policed, policing. n. 1. Also called police force. an organized civil force for maintaining order, preventing and detecting crime, and enforcing the laws. 2. (used with a pl. v.) members of such a force: Several police are… …
50Poppet valve — A poppet valve is a valve consisting of a hole, usually round or oval, and a tapered plug, usually a disk shape on the end of a shaft also called a valve stem. The shaft guides the plug portion by sliding through a valve guide. In most… …
