No. There are many different scales, or gauges, of model trains. For example, an N scale train would be too small to fit on HO scale track.
no
Yes HO is older than 00
yes
Gravity, same as any other train.
No, you must have the same gauge track as your train is made in.
There is no practical limit to the length of train track. Individual rail sections are welded together to make a continuous track. The longest distance you could currently go on the same train without that train having to leave the tracks would be from Kaliningrad on the Baltic Sea to Vladivostok on the Pacific Ocean.
LGB trains are responsible for introducing "G" scale to model railroading. The scale ratio used by LGB is 1:22.5, although other G-scale (and Gauge 1) manufacturers produce products that range from 1:20 to 1:32,[4] and for the most part, all use the same track and are compatible with one another.
They are used so that the railway track doesn't compress or move, and stay's the same so the train doesn't squash the track.
Ship models are sized the same as all models. By scale. A 1:2 scale model of a 100 ft boat would be 50 feet long. A 1:100 scale model of a 100 ft boat would be 10 feet long.
one train enters the tunnel at 7am the other at 7pm
The three types of maglev trains are EDS (electrodynamic suspension), EMS (electromagnetic suspension) and stabilized permanent magnet suspension (SPM). * For EMS, same pole electromagnets in the train repel it away from a magnetically conductive track. * The EDS uses electromagnets on both the track and the train, to push the train away from the track. * SPM uses opposite arrays of permanent magnets to magnetically levitate the train above the track. http://trains.suite101.com/article.cfm/maglev_trains
If you have two magnets they each have a north and south pole. The opposite poles will attract and the same poles will repel. Maglev trains create magnet fields on the track bed and the train of the same polarity. By controlling the generating of the fields you can hold up the train and propel it forward. Since the train is not actually touching a track there is no appreciable friction except that caused by the surrounding air. In a vacuum you would have no friction.