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When a bus becomes a train, which wheels do the work?

When Asa Coast Railway's dual-mode vehicle moves onto rails, its rubber tires do not all become redundant. Steel wheels guide it and help distribute the load, while the rear rubber tires provide the driving force. The Japanese operator's explanation separates three jobs that ordinary wheels often seem to do together: supporting, steering and propelling.

3–5 min

Questions you could explore

  • What changes when the same vehicle has to work on both a road and a railway?
  • How do the rail-guiding wheels and road wheels serve different functions in a dual-mode vehicle?

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Cities and transport3–5 minA boat inside a lock rises when the water around it rises. By filling or emptying the enclosed chamber, a conventional lock brings the boat to the level of the next stretch of canal. The gates contain the water; they do not hoist the boat.

When a bus becomes a train, which wheels do the work? | Speech Topic | speaking.app