Fluid flow on an inclined surface (inclined channel). Using the conservation laws.

Find the volumetric flow rate for the liquid flow inside a very wide inclined channel with the height of h and width of w. Assume it is steady state; fully developed conditions; constant properties, and the angle with the horizon is Ɵ. The flow is downward. Incompressible flow. We are going to use Navier-Stokes (conservation of momentum), and the conservation of mass (continuity equation) to find the velocity profile. If you would like to support the channel please take a look at my T-shirt designs: https://www.teepublic.com/t-shirt/645... Thank you!