Answer:0.1898 Pa/m
Step-by-step explanation:
Given data
Diameter of Pipe
![\left ( D\right )=0.15m](https://img.qammunity.org/2020/formulas/engineering/college/3iuaq7vx29bgschpqspf7j1n85y61rdkda.png)
Velocity of water in pipe
![\left ( V\right )=15cm/s](https://img.qammunity.org/2020/formulas/engineering/college/wg5owd34te3tm31k4ac327lhia8x53aahj.png)
We know viscosity of water is
![\left (\mu\right )=8.90*10^(-4)pa-s](https://img.qammunity.org/2020/formulas/engineering/college/c6nd3mzvj3wgm9h2obkz7ucm0h1ig5g01s.png)
Pressure drop is given by hagen poiseuille equation
![\Delta P=(128\mu \L Q)/(\pi D^4)](https://img.qammunity.org/2020/formulas/engineering/college/u66idtutxbfkdqcifj2td58xh9i4jhb0vt.png)
We have asked pressure Drop per unit length i.e.
![(\Delta P)/(L) =(128\mu \ Q)/(\pi D^4)](https://img.qammunity.org/2020/formulas/engineering/college/tssuvvde027j8d15o9vi0sz1ye900snf3o.png)
Substituting Values
![(\Delta P)/(L)=(128*8.90*10^(-4)*\pi *\left ( 0.15^(3)\right ))/(\pi* 4 *\left ( 0.15^(2)\right ))](https://img.qammunity.org/2020/formulas/engineering/college/e8qyzxvx2tt30z2ae4wl3ycxxph5nuarrs.png)
=0.1898 Pa/m