8.2.1 Fluids in Motion: Streamlines and Continuity Flashcards
Fluids in Motion: Streamlines and Continuity
- The equations of hydrostatics cannot be applied to flowing fluids.
- A useful way to think about streamlines is the paths that parcels of fluid follow. The velocity vectors of the fluid flow are everywhere tangent to the streamlines.
- The equation of continuity for an incompressible fluid is Av= constant.
Which of the following is not a characteristic of an ideal fluid?
An ideal fluid maintains a static-state flow.
True or false?
In laminar flow, the velocity vector of the fluid at any point is tangent to the streamline at that point.
true
Which of the following statements concerning streamlines or laminar flow is incorrect?
In a laminar flow, the pressure, density, and velocity at a given location may change with time.
A cylindircal pipe carrying water slowly widens from a diameter (d1) of 20 cm to a diameter (d2) of 30 cm. If water flows into the pipe at 1 m/s, what is the speed of the water at the exit?
0.44 m / s
Which of the following is not correct with respect to ideal fluids?
The velocity and pressure of an ideal fluid may vary with time.
Applying the conservation of mass to ideal fluids, results in the equation of continuity. Which of the following statements about the derivation of the equation of continuity based on the diagram below is not correct?
The product of the density, the velocity, and the area A1 greater that the product of the density, the velocity, and the area A2.
Which of the following is not correct?
If the velocity of fluid flow at some point changes with time, the fluid flow is nonviscous.
Water flows at a rate of 0.250 L / s (liters per second) through a hose with an internal diameter of 20.00 cm. The nozzle of the hose is a circular opening of diameter 10.00 cm. If 1 ml of water is equivalent to 1 cm3, what is the speed of the water when it emerges?
3.18 cm / s
