Flow rate: An incompressible fluid flows steadily through a pipe that has a change in diameter. The fluid speed at a location where the pipe diameter is 8.0 cm is 1.28 m/s. What is the fluid speed at a location where the diameter has narrowed to 4.0 cm?
A) 0.32 m/s
B) 0.64 m/s
C) 1.28 m/s
D) 2.56 m/s
E) 5.12 m/s

Question

Quizplus · Accepted Answer

The flow rate must be conserved for an incompressible fluid, so A1V1 = A2V2. The area is proportional to the square of the diameter, so (π*(8/2)^2)*1.28 = (π*(4/2)^2)*V2. Solving for V2 gives 5.12 m/s.

Flow Rate: an Incompressible Fluid Flows Steadily Through a Pipe