2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/110512In heavy traffic with congested roadway the maximum traffic flow also depends on length of cars. This is deduced in a simple derivation suited for classroom demonstration as well as homework. The resulting equation demonstrates a new relation to an apparently unrelated area of physics, the maximum ship velocity (hull speed) and explains why traffic is sometimes faster on the slow lane on a congested multi-lane road.3 pages, Submitted to American Journal Of PhysicsPhysics EducationPopular Physicstext