A railroad car of mass 20000 kg and velocity 5.0 m s to the right collides completely elastically in a head on collision with a second car of mass 10000 kg traveling at 1.0 m s to the left and couples to it What fraction of the initial kinetic energy is still retained by the cars after the collision

Nitrogen (n2) undergoes an internally reversible process from 6 bar, 247°c during which pν1.2 = constant. the initial volume is 0.1 m3 and the work for the process is 121.14 kj. assuming ideal gas behavior, and neglecting kinetic and potential energy effects, determine heat transfer, in kj, and the entropy change, in kj/s. show the process on a t-s diagram.