Which has the greatest effect on the flow of fluid through a pipe? That is, if you made a 10% change in each of the quantities below, which would cause the greatest change in the flow rate?
A) the fluid viscosity
B) the length of the pipe
C) the fluid density
D) the radius of the pipe
E) the pressure difference

Question

Quizplus · Accepted Answer

The flow rate of fluid through a pipe is most significantly affected by the radius of the pipe, according to the Hagen-Poiseuille equation, which shows that flow rate is proportional to the fourth power of the radius. This means a small change in the radius has a very large effect on the flow rate.

Which Has the Greatest Effect on the Flow of Fluid