QUESTION As the viscosity of a fluid flowing through a tube is increased, the speed associated with the onset of turbulence:
decreases.
remains the same.
either increases or decreases depending on the diameter.
increases.
either increases or decreases depending on the Reynolds number.
Examine the relation between the Reynolds number and the average speed, viscosity, density, and diameter. If the viscosity is increased, how does the speed for the onset of turbulence change in order to keep the Reynolds number the same?
PRACTICE IT
Use the worked example above to help you solve this problem. Determine the speed at which blood flowing through an artery of diameter 0.24 cm will become turbulent.
3.21 m/s
EXERCISE
HINTS: GETTING STARTED | I'M STUCK!
Determine the speed v at which water at 20° sucked up a straw would become turbulent. The straw has a diameter of 0.0063 m.
1.30
What changes when the fluid changes? You have changed only one quantity. There are more than one that depend on the type of fluid. m/s