a$)$ Find the roughness $(\backslash$epsi $).$

b$)$ Determine the friction velocity on the wall.Fluid Mechanics

$L=20m$

$Q=0,002\frac{m^3}{s}$

$P_p=1000W$

$=1000k\frac{g}{m^3}$

$v=1,02{10}^{-6}\frac{m^2}{s}$

a$)$ Find the roughness $().$

b$)$ Determine the friction velocity on the wall.