4' 8 1/2"
between 15-50 for a school bus
Rail is weighed by the yard...( a yard is 3 feet or 36 inches) If you look at the rail and it says 154 on it then it is "154 pound rail". The lighter 138 pound rail is not as heavy duty as the 154 pound rail. There are many different rail weights. In order to "weigh" the rail you would have to see what pound rail you have then measure that by 3 feet then times that by how long the railroad track is that you are trying to weigh.
15 and 50 feet
there is track width (measured from mid rail to mid rail) and track gauge (measured from inside rail to inside rail. As that is the most important size of track, that is normally the distances referenced to. normal distance for track gauge is 1435 mm
You should be back where signs tells you to stop. If no sign, stay back ten feet from track.
25 feet
rail, railway,track,ehhgine
When stopping for traffic purposes near a railroad track, 50 feet is how far away you're supposed to be, so I assume it's 50 feet or more.
Depends on the railroad, but the most common was 33 feet lengths - same as standard gauge.
for train road
39ft, historically, unless it's CWT track (more modern high-speed rail continuous-welded-track).