Fluids Final Exam Review

True or False: For planar surfaces, the resultant hydrostatic force acts through the centroid of the surface.

• True

• False

Which force ratio properly describes Reynolds number?

• Intertial forces / gravitational forces

• Intertial forces / surface tension

• Intertial forces / viscous forces

• Intertial forces / pressure forces

Water flows steadily through the expanding circular pipe shown below. Which of the following statements is true?

• V₂ = (1/9)V₁

• V₂ = (1/3)V₁

• V₂ = 3V₁

• V₂ = 9V₁

Find the vertical force on the curved surface (R = 2') shown below.

• 3120 lbs

• 3476 lbs

• 1870 lbs

• 2512 lbs

Water flows up the pipe as shown in the figure below. Calculate the amount of head lost between the pressure gauges.

• 2.6 ft

• 5.0 ft

• 6.0 ft

• 9.0 ft

True or False: When using dimensional analysis, you need at least 3 repeating variables to form dimensionless pi groups.

• True

• False

Two balls of the same size are launched with a high velocity, but one ball is smooth, and one is dimpled.

• Smooth; lower skin friction

• Smooth; higher Reynolds number

• Dimpled; lower pressure drag

• Dimpled; less turbulent boundary layer

The box culvert shown below has water flowing through it. Calculate the hydraulic radius.

• 3.6 m

• 3.0 m

• 0.75 m

• 1.5 m

Determine the head loss (in inches) through 18' of 1" diameter dripline in the problem described below.

• h_L = 0.1 in

• h_L = 0.3 in

• h_L = 0.5 in

• h_L = 1.0 in

You can learn the total amount of head in some fluid at a point using either the _____ or _____.

• EGL or HGL

• EGL or pitot-static tube

• EGL or manometer

• pitot-static tube or manometer