PE Exam Practice Problem #50: Water Resources | Mannings Equation - Concept

Welcome to SolvedIn6: Free practice problems for the Professional Engineering Exam! Each question is styled after those created by the NCEES, and is usually solved in under 6 minutes, which is the average time you will have to solve each question on the Professional Engineering Exam.
In this problem, we have two circular sewers that are the same in all respects except for the material that each is constructed from. They are each undergoing a dye test, and we are asked what we think will happen to this dye. Basically, that means we are being asked about the velocity of the flow in each sewer relative to the other. If you’re familiar with Manning’s equation, you might recognize right away that the only term that will be different when finding the velocity of each sewer will be the Manning n value.
This problem can be answered by checking the approximate value of each sewer’s roughness coefficient (n value). The greater the roughness, the slower the velocity, and vice-versa.
If for some reason you didn’t realize it could be determined this easily, you could calculate the velocity in each pipe as well.
If you would like more Water Resources practice problems, please check out the rest of the playlist which this video is part of.
Please note that newer versions of the reference manual may have been released since this video was recorded. The search terms are usually still correct, but the page numbers listed in the video will be different.