Problem 2 A Bingham, incompressible liquid of density p, plastic viscosity u and yield stress to flows down an inclined flat plate of length L and width W. The thickness & of the liquid film is constant and is much smaller than L and W; therefore, the disturbances at the edges of the system (that is, for y = 0, y = L, 2 = 0 and 2 =W) can be assumed to be negligible. So, we assume that: Uz = 0; Vy = vy(x) ; V, = 0 ; p=p(x) In this assumption - which holds if the flow is steady and laminar - the only nonvanishing components of the viscous stress tensor are Try = Tyr. The system is represented in Figure 2. x Edge Vertical direction Edge Figure 2: Sketch of the system. The z axis is normal to the sheet of paper. We can divide the flow domain in two regions. In the first, for 0