> Turning around a track definitely dissipates some heat energy through increased friction with the rails.
No it doesn't, but we're talking about identical spherical frictionless trains in a vacuum.
> Turning around a track definitely dissipates some heat energy through increased friction with the rails.
No it doesn't, but we're talking about identical spherical frictionless trains in a vacuum.
You are also talking about a track with infinite mass because otherwise the reason train can change direction is because it's pushing the track northwards
Obviously! It goes without saying that the track must be infinitely massive and infinitely stiff, mounted on an entirely inflexible infinite plane.
See, now you're talking real physics!