28. Fluid Momentum problems are solved with the aid of twodiagrams of such problems. Explain, list or define items whichwould be included on each of the two diagrams required, anddescribe or show features common to both diagrams. Why are thesetwo drawings typically kept separate?

29. Propellers and turbines are similar in that both act asscrews. Attribute each of the following to Props, Turbines, orBoth:

a. __________Average velocity through the blades, (V1 +V2)/2

b. __________Flow increases in velocity through the blades,increasing momentum of the flow

c. __________Flow decreases in velocity through the blades,decreasing momentum of the flow

d. __________CV Power output represented by Force times Velocityof the control volume

e. __________CV Power output represented by Force time Velocitythrough the blades

f. __________CV Power input represented by Force time Velocitythrough the blades

g. __________CV Power input represented by Force times Velocityinto the control volume

h. __________Efficiency best at a ratio of Vout/Vin = 1/3, 59.3%efficiency at this point

i. __________Efficiency varies greatly with speed, but inairflow, 60-80%, in water 40-60% might be typical forapplications

j. __________Froude’s Theorem applies (also identify applicationof this theorem in this list)

k. __________Bette’s Law applies (also identify application ofthis law in this list)

30. For applications with control volumes having acceleratedmotion, how is Newton’s 2nd Law, the standard momentum equation,expanded to include inertial effects plus local and convectivechanges in momentum through the control volume?