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Text VIII (Questions 36-40)

In 1964 the Japanese began to operate their famous “bullet” train, the Shinkansen, which runs from Tokyo to Nagoya, a 338-kilometer trip that the train is capable of completing in 80 minutes, at a speed of 258 kilometers/hour. In many respects, the Shinkansen represents the high speed train of the future. It runs on a specially constructed “dedicated” track. Each car is separately powered by four electric motors. Each Shinkansen consists of 16 permanently linked 5 cars. The French completed their train grand vitesse (TGV) in 1981. It makes the Paris-Lyon trip - much of which requires climbing extremely steep gradients - at speeds of up to 274 kilometers/hour. It, too, uses “dedicated track” over much of its route, and has permanently linked cars. Unlike the Shinkansen, however, it employs electric-powered locomotives. 10 British High Speed Trains roll on normal tracks, which are also used by freight trains. Their “Tilt” trains travel at high speeds on conventional tracks, but compensate for the sharp curves which the freight trains must take at low speeds by using cars that tilt, or “bank” as they negotiate the turns. steel track and steel wheels altogether. Instead, it glides silently over a raised track, or guideway, lifted a few inches over the guideway surface by a magnetic field. Both Germany and Japan have worked on Maglev prototypes for several years. The Japanese are experimenting with a system whereby the train is raised up off the track by repulsive magnets within the guideway. The Germans’ attractive system uses electromagnets set on the bottom of the train’s undercarriage 20 wings that wrap around and underneath the guideway. When current flows through the magnets, they are drawn toward a steel rail on the underside of the guideway, and the train lifts. Various other magnetic systems guide the train within the guideway walls, and brake or add speed. The most revolutionary new train design, the Maglev (Magnetic Levitation), eliminates the 15

מרתון ספר

363

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