Chapter 23, Problem 26P

The velocity y (m/s) of air fl owing past a flat surface is measured at several distances $y\left(\text{m}\right)$ away from the surface. Determine the shear stress $\tau \left({\text{N/m}}^{\text{2}}\right)$ at the surface $\left(y=0\right)$, using Newton's viscosity law

$\tau =\mu \frac{dv}{dy}$

Assume a value of dynamic viscosity $\mu =1.8\times {10}^{-5}\text{N}\cdot {\text{s/m}}^{\text{2}}$.

y, m	0	0.002	0.006	0.012	0.018	0.024
v, m/s	0	0.287	0.899	1.915	3.048	4.299