Question: Find the velocity profile, average velocity, and free surface velocity for a Newtonian fluid flowing down a vertical wall of length L. Use a control volume (CV) of thickness Ax inside the fluid and measure x from the free surface. Remember that because the liquid surface is "free" (unbounded physically) at x = 0, the pressure at all points, vertical as well as horizontal, is atmospheric.
![804_Free surface.png](https://secure.tutorsglobe.com/CMSImages/804_Free surface.png)
2. Derive the equations for the velocity distribution and for the pressure drop in laminar, Newtonian flow through a slit of height yo and infinite width.