Question

A wall shear stress of 40 Pa exists in a laminar flow in a 12 cm diameter pipe. At a distance of 2 cm from the wall, what will be the shear stress?

• A. 22.2 Pa
• B. 24.0 Pa
• C. 26.7 Pa
• D. 28.0 Pa

Answer 1

The correct option is C 26.7 Pa

$\tau ={\tau }_0\frac{r}{R}=\left(40\text{Pa}\right)\frac{4}{6}=26.7\text{Pa}$