hydraulic machines MCQs – Page 2

Practise focused hydraulic machines questions with marked answers for exam preparation and subject revision.

hydraulic machines Mcqs
21. Head developed by a centrifugal pump depends on___________________?
comments icon0
A. A. and B. above

B. fluid density

C. impeller diameter

D. speed

E. type of casing

22. Specific speed for reaction turbines ranges from___________________?
comments icon0

A. 250 to 300

B. 10 to 100

C. none of the above

D. 80 to 200

E. 0 to 4.5

23. In a centrifugal pump casing, the flow of water leaving the_______________?
comments icon0

A. centrifugal

B. radial

C. rectilinear

D. vortex

E. radial

24. A hydraulic accumulator normally consists of________________?
comments icon0

A. special type of pump with storage device and a pressure regulator

B. two cylinders, two rams and a storage device

C. a cylinder, a piston, storage tank and control valve

D. a cylinder and a ram

E. two co-axial rams and two cylinders

25. The optimum value of vane exit angle for a centrifugal pump impeller is_________________?
comments icon0

A. 10-15

B. 30-40

C. 50-60

D. 20-25

E. 80-90.

26. According to fan laws, at constant pressure, the speed capacity and power vary_________________?
comments icon0

A. as square of density

B. as square root of density

C. inversely as density

D. inversely as square root of density

E. directly as the air or gas density

27. Casting of a centrifugal pump is designed so as to minimize________________?
comments icon0
A. loss of kinetic energy

B. cavitation

C. friction loss

D. starting time

E. static head

28. Impulse turbine is generally fitted______________________?
comments icon0

A. about 2.5 m above the tail race to avoid cavitation

B. about 2.5 m below the tail race to avoid cavitation

C. at the level of tail race

D. slightly below the tail race

E. little above the tail race
29. According to fan laws, at constant speed and capacity, the pressure and power vary_____________________?
comments icon0

A. as square of density

B. inversely as density

C. as square root of density

D. directly as the air or gas density

E. inversely as square root of density

30. According to fan laws, for fans having constant wheel diameter, the air or gas capacity varies______________________?
comments icon0
A. directly as fan speed

B. cube of fan speed

C. square of fan speed

D. none of the above

E. square root of fan speed

31. The discharge through a reaction turbine with increase in unit speed____________________?
comments icon0

A. first increases and then decreases

B. remains unaffected

C. increases

D. first decreases and then increases

E. decreases
32. The hydraulic turbines are also known as : ___________?
comments icon0

A. steam turbines

B. combustion turbines

C. water turbines

D. Gas turbines

33. For very high discharge at low pressure such as for flood control and irrigation applications, following type of pump is preferred_________________?
comments icon0

A. reciprocating

B. none of the above

C. centrifugal

D. mixed flow

E. axial flow
34. Guide angle as per the aerofoil theory of Kaplan turbine blade design is defined as the angle between_________________?
comments icon0

A. lift and tangential force

B. drag and resultant force

C. lift and resultant force

D. resultant force and tangential force

E. lift and drag

35. Francis turbine is best suited for_____________________?
comments icon0
A. medium head application from 24 to 180 m

B. all types of heads

C. low head installation up to 30 m

D. none of the above

E. high head installation above 180 m

36. A turbine pump is basically a centrifugal pump equipped additionally with_________________?
comments icon0

A. totally submerged operation facility

B. inlet guide blades

C. vaned diffusion casing

D. adjustable blades

E. backward curved blades

37. Low specific speed of turbine implies it is__________________?
comments icon0

A. propeller turbine

B. none of the above

C. any one of the above

D. Francis turbine

E. impulse turbine
38. The maximum number of jets generally employed in impulse turbine without jet interference is________________?
comments icon0

A. 16

B. 4

C. 6

D. 8

E. 12

39. If a pump is handling water and is discharging a certain flow Q at a constant total dynamic head requiring a definite B.H.P., the same pump when handling a liquid of specific gravity 0.75 and viscosity nearly same as of water would discharge_____________________?
comments icon0
A. same quantity of liquid

B. none of the above

C. 1.5 Q

D. 0.75 Q

E. Q/0.75

40. Medium specific speea of turbine implies it is___________________?
comments icon0

A. none of the above

B. propeller turbine

C. Francis turbine

D. any one of the above

E. impulse turbine