rail current switch
41Relay — This article is about the electrical component. For other uses, see Relay (disambiguation). Automotive style miniature relay, dust cover is taken off A relay is an electrically operated switch. Many relays use an electromagnet to operate a… …
42TGV — The TGV ( train à grande vitesse , French for high speed train ) is France s high speed rail service developed by GEC Alsthom (now Alstom) and SNCF, the French national rail operator, and operated primarily by SNCF. Following the inaugural TGV… …
43Electric motor — For other kinds of motors, see motor (disambiguation). For a railroad electric engine, see electric locomotive. Various electric motors. A 9 volt PP3 transistor battery is in the center foreground for size comparison. An electric motor converts… …
44Power supply unit (computer) — Power supply unit with top cover removed A power supply unit (PSU) supplies direct current (DC) power to the other components in a computer. It converts general purpose alternating current (AC) electric power from the mains (110 V to… …
45environment — environmental, adj. environmentally, adv. /en vuy reuhn meuhnt, vuy euhrn /, n. 1. the aggregate of surrounding things, conditions, or influences; surroundings; milieu. 2. Ecol. the air, water, minerals, organisms, and all other external factors… …
46Cab signalling — is a railroad safety system that communicates track status information to the train cab (driving position), where the engineer or driver can see the information. The simplest systems display the trackside signal aspect (typically, green, yellow… …
47Streetcars in Washington, D.C. — This article refers to the streetcars that existed in Washington prior to 1962. For information on the proposed new streetcar lines, see DC Streetcar. Washington Streetcars 15th Street NW in the early 20th century Info …
48United Kingdom — a kingdom in NW Europe, consisting of Great Britain and Northern Ireland: formerly comprising Great Britain and Ireland 1801 1922. 58,610,182; 94,242 sq. mi. (244,100 sq. km). Cap.: London. Abbr.: U.K. Official name, United Kingdom of Great… …
49Railway signal — Not to be confused with Railway signalling. A signal is a mechanical or electrical device erected beside a railway line to pass information relating to the state of the line ahead to train/engine drivers. The driver interprets the signal s… …
50Railway signalling — Not to be confused with Railway signal. A gantry of British semaphore signals seen from the cab of a steam locomotive Railway signalling is a system used to control railway traffic safely, essentially to prevent trains from colliding. Being… …
