# A more rigid explanation of “path of least resistance”

In order to try to understand the centripetal force and more specifically how it works for cars, I watched this YouTube video:

Could anyone please explain this in a more "mechanically rigid" way? It seems like $F_s$, the static friction force, works perpendicular to "the path of least resistance", so I assume it is a force of some sort, but the force does not seem to be centripetal from his explanation.