3. A liquid layer separates two plane surfaces as show. The lower surface is stationary and the upper surface moves downward at constant speed V. The moving surface has width w, perpendicular to the plane of the diagram (w>>L). The incompressible liquid layer, of density p, is squeezed from between the surfaces. Assume the flow is uniform at any cross section and neglect viscosity as a first approximation. 2 Use a suitably chosen control volume, please show that u=Vx/b within the gap, where b=bo-Vt, and obtain an algebraic expression for the acceleration of a fluidic particle located at x. Determine the pressure gradient OP, in the liquid layer. Find the pressure distribution p(x). др dx' Obtain an expression for the net pressure force that acts on the upper flat surface. 2) Please solve the same problem with the varied channel gap. 2) b y L