Question

Let's say you bought a plywood 2.5 m wide and 2 m long and placed it on the roof of your car.
The boundary layer formed when driving the car towards the house is laminar along the plate and the air flow of the plate
It is assumed that it is aligned in parallel. The boundary layer thickness at the end of the plate (escape edge) is 12.5 mm
by;
a) Local speed at the point of the plate (x, y) = (0.5 m, 2.5 mm), u
b) Local shear stress of the plate at the point (x, y) = (0,5 m, 2,5 mm), τx (Pa)
c) Find the total drag force on the plate, D (ρ air = 1.2 kg / m3, ν = 1.510-5 m2 / s).

Answer 1