3. [2 points] Water, an incompressible fluid, flows through a pipe such that the flow is fully developed. The first section of the pipe has smooth walls, the second section has rough walls as shown. Both sections have the same diameter D and length L, and the flow rate is also same. Clearly explaining using fluid dynamics concepts, compare the pressure drops in the two sections (greater than, less than, or equal) if smooth rough (a) The flow is laminar throughout. (b) The flow is turbulent throughout. Write <, > or = for each case in the box below. Explain how do you know for each case. [[1 point] Laminar: AP smooth. [1 point] Turbulent: APS smooth. APro rough APrough

Fig: 1