Is there a physical limit for the length of a train?

Question

Assume you can hook every locomotive and car Union Pacific owns up into a single gigantic freight train. Safety and laws aside, would it work?

In: Physics

Answer 1

You could get pretty far with distributed power. Just throw a few engines in every couple dozen rail cars. The limitations of how far apart those cars can be depends a lot more on the size of the yard and the build area than it does the physical limits of the train. Once you get to the length where you need to account for the time it takes for signals to reach the other engines from the control point, you’re well beyond the circumference of the Earth, let alone the longest continuous piece of track