The velocity profile for a laminar boundary layer is given by $\frac{u}{U}=sin \left ( \frac{\pi }{2} \frac{y}{8} \right )$ where u is the velocity at a distance y from the plate. U is the free stream velocity is the boundary layer thickness, determine expressions in terms of Reyonld’s number for the following:
(i) boundary layer thickness
(ii) drag force on both sides of the plate
(iii) co-efficient of drag