Pipes in your system will have a C-Factor to help determine this loss. This is a measure of the roughness of the interior of the pipe that creates this friction. Different types of piping will have a different C-Factor, and the higher the C-Factor, the smoother the pipe.
A motif is a literary term that is an idea, object, or concept that repeats itself throughout a text. A motif gives clues to theme or reinforces ideas an author wants to emphasize. A motif generally reinforces the theme of the text. A motif must be repeated throughout a text to be considered a motif.
Motifs are used to establish a theme or a certain mood; they have a symbolic meaning. It's typically pretty clear when a writer is using a motif. They're not usually associated with hidden meanings because the writer wants you to recognize them. They play a role in defining the makeup of a narrative.