Roller coaster dynamics—From point particles to a continuum model using Lagrange density

Analyzing the motion of a roller coaster allows for an instructive introduction of various theoretical concepts in a concrete and enjoyable context. We start by modeling the roller coaster train as a point particle. We then develop more realistic models for the train and finally we show how to introduce a continuum limit in a simple way. These studies instructively illustrate the relationships between different formalisms (Newtonian mechanics, Lagrangian mechanics of the first and second kind, as well as continuous Lagrangian mechanics using a Lagrangian density). We derive the equations of motion in all considered models and calculate the forces acting on the track and on the passengers. Numerical results are also provided and discussed.