where is a simple gear train used in real life
Automobile drivetrains
title: Rail transport modelling text: Rail transport modelling Railway modelling (UK, Australia and Ireland) or model railroading (US and Canada) is a hobby in which rail transport systems are modelled at a reduced scale. The scale models include locomotives, rolling stock, streetcars, tracks, signalling and landscapes including: countryside, roads, bridges, buildings, vehicles, urban landscape, model figures, lights, and features such as rivers, hills, tunnels, and canyons. The earliest model railways were the 'carpet railways' in the 1840s. Electric trains appeared around the start of the 20th century, but these were crude likenesses. Model trains today are more realistic, in addition to being much more technologically title: Mall train text: Mall train A Mall Train or Kiddie train is an attraction resembling a small train that may or may not run on tracks. Trackless trains are popular. They are characterized by fake side wheels wheels that do not move and permanently connected cars. These trains are the most widely used and can be found at most malls. Such trains are widely modeled after steam locomotives used during the mid-1800s. They are replicas and are powered by Internal combustion engines or electricity. A major manufacturer is Loco-Motives LLC These trains move on tracks. They are more popular at amusement parks. However, title: Track gauge in the United States text: 1876. The New England railways were similarly standard-gauged in the 1870s. In the 1960s, the gauge was selected for use in the Bay Area Rapid Transit system, serving the San Francisco Bay Area; it is the only place in the United States where this gauge is in use. The rapid transit segment of the system covers of double track in revenue service. and are commonly known as Pennsylvania trolley gauge because it was originally used by railroad lines in the state of Pennsylvania. Unlike other broad gauges, it remains in use in a number of urban rail transit systems: In title: Toy train text: Toy train A toy train is a toy that represents a train. It is distinguished from a model train by an emphasis on low cost and durability, rather than scale modeling. A toy train can be as simple as a pull toy that does not even run on track, or it might be operated by clockwork or a battery. Many of today's model trains might be considered as toy ones as well, providing they are not strictly scale ones in favor of a robustness appropriate for children. The first widely adopted standards for toy trains running on track were introduced title: 3 ft gauge railways text: 3 ft gauge railways Three foot gauge railways have a track gauge of or 1 yard. This gauge is a narrow gauge and is generally found throughout North, Central, and South America. In Ireland, many secondary and industrial lines were built to gauge, and it is the dominant gauge on the Isle of Man, where it is known as the "Manx Standard Gauge". Modern gauge railways are most commonly found in isolated mountainous areas, on small islands, or in large-scale amusement parks and theme parks (see table below). This gauge is also popular in model railroading (particularly in G scale),