The figure below represents a simple network with one origin…
The figure below represents a simple network with one origin (O), one destination (D), two internal nodes (1 and 2), and five network links. In this case, the link travel times vary linearly as a function of the flow on the links as shown in the figure. The demand for travel between the origin and destination is 100 trips. Consider a situation in which 65 vehicles choose route O-1-D (i.e. q1 = q4 = 65) and the rest (i.e., 35 vehicles) choose route O-2-D. No one chooses O-2-1-D. Show using appropriate calculations that this situation does NOT represent user equilibrium. At equilibrium, will the flow on O-1-D be greater than 65 or lesser than 65? Note that you do not have to solve the equilibrium flows.