GURUKUL STUDY CENTRE FOR TECHNICAL SERVICE EXAMINATION MECHANICAL ENGINEERING

GARIA STATION, KOLKATA- 84 PSC:- FLID MECHANICS

18 M- 9874074233, 7003482988, 8617277161 NAME-
R- W- T-
1.
Dynamic viscosity
Kinematic viscosity is equal to (A) (B) Dynamic viscosity x Density
Density
Density 1
(C) (D)
Dynamic viscosity ( Dynamic viscosityx Density)
2
v 2−v 22 ( v −v 2 )
2. Head loss due to a sudden enlargement in a pipe is (A) 1 (B) 1 (C)
2g 2g
2 2 2
( v 1−v 2 ) (D) v 1−v 2
g g
3. The point in the immersed body through which the resultant pressure of the liquid be taken to act is known as
(A) Metacenter (B) Centre of pressure (C) Centre of buoyancy (D) Centre of gravity
4. Rain drops are spherical because of (A) Viscosity (B) Air resistance (c) Surface tension
(D) Atmospheric pressure
5. In steady flow of a fluid, the acceleration of any fluid particle is (A) Constant (B) Variable (C) Zero
(D) Never zero
6. For measuring flow by a venturimeter, it should be installed in (A) Vertical line (B) Horizontal line
(C) Inclined line with upward flow (D) In any direction and in any location
7. Capillarity is due to (A) Cohesion (B) Adhesion (C) Adhesion and Cohesion (D) Molecular structure
8. A Piezometer cannot be used for pressure measurement in pipes when (A)pressure difference is low.
(B) velocity is high. (C) fluid in the pipe is a gas. (D) fluid is highly viscous.
9. Units of Kinematic viscosity are (A)M²/Sec (B) kg/sec/m² (C) Newton-sec/m²
(D) Newton-sec/m
10. Which of the following is correct? (A) Absolute pressure = Gauge pressure + Atmospheric pressure
(B) Gauge pressure = Absolute pressure +Atmospheric pressure (C) Atmospheric pressure = Absolute
pressure + Gauge pressure (D) Absolute pressure = Gauge pressure -Atmospheric pressure
11. The value of pressure represented by 1mm of Hg is equal to (A) 1.333 N/m² (B) 13.33 N/m²
(C) 133.3 N/m (D) 1333 N/m²
12. A vessel of 4m³ contains oil which weighs 30 KN. The specific weight of the oil is
(A) 4.5 kN/m³ (B) 6 kN/m³ (C) 7.5 kN/m³ (D) 10 kN/m³
13. The unit of surface tension is (A) N/m (B) N/m² (C) N/m³ (D) N-m

1.A 2.B 3.B 4.C 5.C 6.D 7.C 8.C 9.A 10.A 11.C 12.C 13.A

2016
14. Which of the following is correct?
(A) Absolute pressure = Gauge pressure + Atmospheric pressure
(B) Gauge pressure = Absolute pressure + Atmospheric pressure
(C) Atmospheric pressure = Gauge pressure + Absolute pressure
(D) None of the above
15. A differential manometer is used to measure
(A) atmospheric pressure. (B) pressure in pipes and channels.
(C) pressure in venturimeter. (D) difference of pressures between two points in a pipe.
16. A vertical wall is subjected to a pressure due to one kind of liquid, on one of its sides. The total pressure on the wall
per unit length is
(A) WH (B) wH/2 (C) WH2/2 (D) WH2/3
w-Specific weight of liquid, H= height of liquid.
17. A flow in which the quantity of liquid flowing per second is not constant is called
(A) Streamline flow (B) Turbulent flow (C) Steady flow (D) Unsteady flow
18. The imaginary line drawn in the fluid in such way that the tangent at any point gives the direction of motion at that
point is known as- (A) Path line (B) Stream line (C) Streak line (D) Potential line
19. The Bernoulli's Equation is based on the assumption that
 GURUKUL STUDY CENTRE FOR TECHNICAL SERVICE EXAMINATION MECHANICAL ENGINEERING
GARIA STATION, KOLKATA- 84 PSC:- FLID MECHANICS
M- 9874074233, 7003482988, 8617277161 NAME-
R- W- T-
(A) there is no loss of energy of the liquid flowing.
(B) the velocity of flow is uniform across any cross section of the pipe.
(C) no force except gravity force acts on the fluid.
(D) All of the above
20. Ventúrimeter is used to
(A) Measure the velocity of a flowing fluid. (B) Measure the pressure of a flowing fluid.
(C) Measure the discharge of liquid flowing in a pipe.
(D) Measure the pressure difference of liquid flowing between two points in a pipeline.
21. The theoretical velocity of jet at vena contracta is
(A) 2gH (B) H(2g)1/2 (C) 2gH1/2 (D) (2gH) 1/2
22. The discharge over a rectangular notch is
(A) Inversely proportional to H3/2 (B) directly proportional to H3/2
5/2
(C) Inversely proportional to H (D) directly proportional to H5/2
23. The hydraulic mean depth for a circular pipe of diameter 'd' is
(A) d/6 (B)d/4 (C) d/2 (D) d
24. The discharge of a centrifugal pump is given by
(A) Q= π D V f (B) Q= π b V f (C) Q= π Db V f (D) Q= DbV f
D,b= diameter and of impeller, Vf =Velocity of flow at inlet
25. Multi-stage centrifugal are used to
(A) give high discharge (B) produce high heads (C) pump viscous fluid (D) All of the above
26. Delivery head of a centrifugal pump is
(A) directly proportional to diameter of its impeller.
(B) inversely proportional to diameter of its impeller.
(C) proportional to (diameter) of its impeller.
(D) inversely proportional to (diameter) of its impeller.
27. Which ratio gives the Reynolds number?
(A) Inertia force to viscous force (B) Inertia force to gravity force
(C) Inertia force to pressure force (D) Inertia force to viscous force
28. The value of bulk modulus of a fluid is required to determine
(A) Reynolds’s number (B) Froude's number (C)Mach number (D)Euler number
29. If the NPSH requirement for the pumps not satisfied, then
(A) efficiency will be low. (B) no flow takes place. (C) cavitation will be formed.
(D) excessive power will be consumed.
30. Which type of pump is different from others in the same group?
(A) Screw pump (B) Gear pump (C) Plunger pump (D) Cam and piston pump
31. A point in a compressible flow where the velocity of fluid is zero is called
(A) Critical point (B) Vena contracta (C) Stagnation point (D) None of the above
14.A 15.D 16.C 17.D 18.B 19.D 20.C 21.D 22.B 23. 24.C 25.B 26.C 27.A 28. 29.C 30.C 31.C
B C

2007
32. In a centrifugal pump installation while starting , the position of delivery valve is
(A) fully open (B) fully closed (C) half open (D) less than half open
33. The flow will be turbulent flow, if the Reynolds’s number of the particular flow is
(A) In between 2000 and 4000 (B) More than 4000 (C) Less than 2000
(D) None of the above
34. The general energy equation is applicable to
(A) Steady flow (B) Unsteady flow
(C) Non-uniform flow (D) Laminar flow
35. The overall efficiency of a centrifugal pump is
 GURUKUL STUDY CENTRE FOR TECHNICAL SERVICE EXAMINATION MECHANICAL ENGINEERING
GARIA STATION, KOLKATA- 84 PSC:- FLID MECHANICS
M- 9874074233, 7003482988, 8617277161 NAME-
R- W- T-
Actual Dischargs Oups of the pump(water horse power) Output of the pump
(A) (B) (C)
Theoretical Dacharge Input power of the pump Input H P of the Impeller
H . P . of the Impeller
(D) drive the Power ¿
H .P¿

36. The slip of a reciprocating pump may be

(A) Positive (B) Negative (C) Zero (D) All of the above
37. Inverted differential manometer is used for
(A) measuring difference of low pressure where accuracy is the prime consideration
(B) measuring difference of pressure in two different pipes
(C) measuring small pressure (D) measuring negative pressure
38. The specific speed for reaction turbine range is from
(A) 3-7 (B) 10-20 (C) 25-80 (D) 60-300
39. The specific speed Ns of a centrifugal pump is given by
N × √Q N × √Q N × √Q N × √Q
(A) (B) (C) (D)
H 5/ 4 H H 3/ 4 H 2 /3
where N = speed of the impeller, H= lift of the pump, Q= discharge of the pump

40. A pitot tube is an instrument to determine

(A) discharge (B) pressure (C) velocity of flow (D) energy
41. A pitot tube was inserted in a pipe to measure the velocity of water in it. If the water rises in the tube is 200 mm from
the surface, the velocity of water is
(A) 3.92 meter/sec (B) 1.98 meter/sec. (C) 2.59 meter/sec. (D) None of the above
42. State which one of the following statements is not correct for submersible pumps:
(A) A submersible pump may be dry waste type (B) A submersible pump may be waste water type(C) The
motor of the submersible pump is always hung below the pump
(D) Submersible pump is not economical in deep wells since the pump requires the use of long vertical shafts
43. State which one is not correct for an axial flow pump:
(A) The shaft of axial flow pump may be horizontal (B) The shaft of axial flow pump may be vertical
(C) The shaft of axial flow pump may be inclined
(D) The flow ratio of axial flow pump is smaller than centrifugal pump of same capacity
44. A Francis turbine is
(A) Inward flow reaction turbine (B) Inward flow impulse turbine
(C) Outward flow reaction turbine (D) Outward flow impulse turbine
45. The discharge through a venturimeter is given by the formula

(A) Q=C ×
a1a2
× √ a1−a2
2 2
(B) Q=C ×
√ a −a × √2 gh
2
1
2
2
(C) Q=C ×
a1 ×a 2
× √2 gh
√ 2 gh a a
1 2 √ a −a
2
1
2
2
(D) None of the above
where C = co-efficient of venturimeter , a 1= area in large section of the meter in appropriate unit, a 2= area of
throat in appropriate unit, h = difference of pressure head in appropriate unit
32.B 33.B 34.C 35.C 36.D 37.D 38.C 39.C 40.C 41.B 42.D 43 44.A 45.C

2004
46. The range of coefficient of discharge (cd) for a venturimeter is
(a) 0.6 to 0.7 (b) 0.7 to 0.8 (c) 0.8 to 0.9 (d) 0.95 to 0.99
47. In centrifugal pumps, maximum efficiency is obtained when the blades are
(a) Straight (b) Bent forward (c) Bent backward (d) Radial
46.D 47.C
2003
48. The height of water column equivalent to a pressure of 2 kgf/cm 2 is
(a) 10 m (b) 2 m (c) 10 m (d) 6 m
49. The Bernoulli's equation is applicable only when the flow is
(A) steady ir-rotational, incompressible and non-viscous
 GURUKUL STUDY CENTRE FOR TECHNICAL SERVICE EXAMINATION MECHANICAL ENGINEERING
GARIA STATION, KOLKATA- 84 PSC:- FLID MECHANICS
M- 9874074233, 7003482988, 8617277161 NAME-
R- W- T-
(B) steady, non-viscous and incompressible flow in a stream tube
(c) steady and ir-rotational (d) ir-rotational and non-viscous
50. A fluid is a substance that
(A)always expands and fills any container
(B)is practically incompressible
(C)cannot be subjected to shear force
(D)cannot remain at rest under the action of any shear force
51. For sharp-edged orifices the average value of discharge coefficient varies between
(a) 0.60 to 0.64 (b) 0.70 to 0.80 (c) 0.40 to 0.50 (d) C.50 to 0.64
52. The continuity equation of flow is based on the principle of conservation of
(a) pressure (b) velocity (c) energy (d) none of the above
53. The pitot tube is a device used for
(a) measuring only average velocity of flow (b) measuring the pressure at a point
(c) measuring the velocity at a point in the flow (d) measuring the pressure difference in pipe flow
54. The critical Reynolds number for pipe flow is around
(a) 200 to 300 (b) 2000 to 3000 (c) 1000 to 4000 (d) all of the above
55. For a fluid flowing through a pipe, power loss due to friction varies
(a)directly as the fluid velocity (b) inversely as the length of the pipe
(c) as the square of the fluid velocity (d)all of the above
56. a reciprocating pump runs with delivery valve closed, following...............n most of the cases:
(A) The delivery pipe bursts
(B) The motor-fuse blows up
(C) The vater inside the pump gets heated
(D) All of the above
57. An air vessel is fitted to a reciprocating pump
(a) to increase the work done (b) to eliminate cavitation
(c) to reduce the work done (d) so that it results in non-uniform discharge
58. Specific speed of a centrifugal pump is given by
N √Q N √Q N √P Q
(a) (b) (c) (d)
H 5/ 4 H 3/ 4 H 5 /4 ND 3
59. Pump used for highly viscous liquid belongs to the category of
(a) plunger pump (b) centrifugal pump (c) reciprocating pump (d) screw pump
60. Submersible pumps are used for
(a) positive displacement of liquid (b) oil fields (c) low heads
(d) both (a) and (b)
61. Priming is not required for
(a) gear pump (b) plunger pump (c) hand pump (d) submersible pump
62. Turbine pump is used for
(a) high head (b) household applications
(c) pumping cooling water in large MW power plants (d) none of the above
63. Vibration in turbine pump installation is related to
(a) bent shafting (b) misalignment (c) rotational element unbalance
(d) all of the above

48.20 49.A 50.D 51.A 52.D 53.C 54.B 55.C 56.D 57.C 58.B 59.D 60.D 61.D 62.A 63.D
M

2002
64. Air vessels are used in reciprocating pump for
(a) Uniform Velocity (b) Uniform discharge (c) Uniform discharge and velocity
(d) None of the above
65. Deep well pump is always kept with shaft in
(a) Vertical position (b) Horizontal position (c) Inclined position
 GURUKUL STUDY CENTRE FOR TECHNICAL SERVICE EXAMINATION MECHANICAL ENGINEERING
GARIA STATION, KOLKATA- 84 PSC:- FLID MECHANICS
M- 9874074233, 7003482988, 8617277161 NAME-
R- W- T-
(d) None of the above
66. In a submersible pump the electric motor is placed
(a) On the ground (b) In the vicinity of the pump (c) Deep below the pump
(d) None of the above

67. For laminar flow through a circular pipe, the friction factor (f) is related to Reynolds number (Re) by
1 16 64 64
(a) f = (b) f = (c) f = (d) f =
ℜ ℜ ℜ ℜ
68. For sharp-edged orifices the average value of discharge coefficient varies between
(a) 0.4 to 0.5 (b) 0.6 to 0.65 (c) 0.7 to 0.8 (d) 0.8 to 0.9
69. Pump used for highly viscous liquid belongs to the category of
(a) Screw pump (b) Turbine pump (c) plunger pump (d) Centrifugal pump
70. The continuity equation of flow is based on the principle of conservation of
(a) Momentum (b) Energy (c) Mass (d) Pressure
71. A pilot tube measures the difference between
(a) Dynamic pressure and static pressure (b) Static pressure and dynamic pressure
(c) Total pressure and dynamic pressure (d) Total pressure and static pressure
72. The buoyant force acting on a floating body passes through the
(a) Centroid of the displaced volume (b) Metacenter of the body
(c) Centre of gravity of the body (d) Centroid of the floating volume of the body
73. Priming is not required in
(a) Gear pump (b) Plunger pump (c) Hand pump (d) Submersible pump
74. Vibration in turbine pump installation is not related to
(a) Bent shafting (b) Rotational element unbalance (c) Misalignment
(d) Accelerometer
75. In submersible pumps, motors are typically mounted below the pumps to
(a) Take the thrust of rising liquid column (b) Ensure better balancing of pumps
(c) Ensure cooling of the motors by continuous flow of liquid (d) Avoid short-circuit by liquid

76. For a given centrifugal pump

(a) Head varies directly as speed (b) Power varies as the square of speed
(c) Discharge varies as the square of speed (d) Discharge varies directly as the speed
77. Which of the following statements is not true for a vertical turbine pump?
(A)The pump is driven through a V-belt drive driven by an electric motor located on ground level
(b) It is a multi-stage pump (c) Pump impellers are placed below the water level
(d) The pump shaft is coupled to a long line shaft enclosed in a pipe
78. For a fluid flowing through a pipe, power loss due to friction varies
(a) Directly as the fluid velocity (b) As the square of the fluid velocity
(c) As the cube of the fluid velocity (d) Inversely as the length of the pipe
79. Air Vessels in a reciprocating pump are used to
(a) Increase pump head (b) Increase pump discharge
(c) Reduce accelerating head to minimum (d) Save pump from cavitation
80. High speed centrifugal pump with radium at outlet specific speed
(a) 10 to 30 (b) 30 to 0 (c) 50 to 80 (d) 150 to 160
81. Discharge (Q) of a centrifugal pump is given by
(a) π DV1 (b) π D.b.V1 (c) π .d.v₁ (d) D. b.V1
Where D = Dia of impeller at inlet, d = Width of impeller at inlet, V = Velocity of flow at inlet
82. The pump preferred for flood control and irrigation applications are
(a) Centrifugal pumps (b) Axial flow pumps (c) Mixed flow pumps
(d) Centrifugal pump
83. For flow through a horizontal pipe, the pressure gradient dx in the flow direction is
(a) + Ve (b) One (c) Zero (d) - Ve
84. The rise of oil in the wick of an oil lamp is due to
(a) Pressure difference between the oil and the environment (b) Viscosity of coil
(c) Adhesion on between the oil and wick material (d) Capillary action
85. Pumps not covered under reciprocating type is
 GURUKUL STUDY CENTRE FOR TECHNICAL SERVICE EXAMINATION MECHANICAL ENGINEERING
GARIA STATION, KOLKATA- 84 PSC:- FLID MECHANICS
M- 9874074233, 7003482988, 8617277161 NAME-
R- W- T-
(a) Single acting piston pump (b) Double acting plunger pump
(c) Bucket type hand pump (d) Single stage volute type pump deals with
86. In a reciprocation pump slip is generally
(a) Zero (b) Positive (c) Negative (d) None of the above

64.C 65.A 66.C 67.C 68.B 69.A 70.C 71.B 72.A 73.D 74.D 75.C
76.D 77.A 78.B 79.C 80.C 81.B 82.B 83. 84.D 85.D 86.C
2001
87. A floating body is in neutral equilibrium when
(a) metacenter is below the C.G. (b) metacenter coincides with the C.G.
(c) metacenter is above the C.G. (d) none of the above

88. A flow, in which the quantity of liquid flowing per second is not by
(a) Turbulent flow (b) Unsteady flow (c) Steady flow (d) Streamline flow

89. Total head of a liquid particle in motion can be represented by

2 2 2
V P V P V P
(a) H=Z - + (b) H=Z + − (c) H=Z + + (d) none of the above
2G w 2g w 2g w
90. For accurate measurement of fluid pressure we require
(a) Differential manometer (b) Piezometer (c) Inclined manometer
(d) none of the above
91. State the correct relation :
Cv Cc
(a) Cd = (b) Cd = (c) Cd = Cv x Cc (d) none of the above
Cc Cv
92. Reynolds’s number is less than 2000, the flow is
(a) Turbulent (b) Laminar (c) neither turbulent nor Laminar
(d) none of the above
93. For a centrifugal pump,
(a) head varies inversely as the speed (b) power varies as the square of the speed
(c) discharge varies directly as the speed (d) discharge varies as the square of the speed
94. Deep well turbine pump, have impeller in
(a) Series (b) Parallel (c) Half in series and half
(d) none of the above in parallel
95. Specific weight of a liquid having a volume 4 cu. m and weighing 3000 kg is
(a) 750 kg/m³ (b) 76-5 kg/sec²/m4 (c) 0.75 (d) none of the above
96. Instrument used for measuring the flow of liquid through a pipe is called
(a) Manometer (b) Venturimeter (c) Barometer (d) Ammeter

97. An opening in the side or bottom of a vessel containing liquid through which the liquid flows out is called
(a) Notches (b) Channel (c) Orifice (d) Tube
98. Head loss of the water at the entrance to pipe from a large vessel is equal to
2
0.5 V 0.5 V 0.5 V
(a) (b) (c) (d) none of these
2g g 2g
99. Air vessels are fitted on the suction as well as on the delivery side near the reciprocating pump cylinder for
(a) increasing the accelerating head (b) running the pump at a higher speed
(c) increasing the possibility of separation (d) none of the above
100. Most of the pumps used for agricultural purpose are
(a) Reciprocating pump (b) Single stage centrifugal pump (c) submersible pump
(d) none of the above
101. The mercury does not wet the glass due to its property known as
(a) Viscosity (b) Surface tension (c) Cohesion (d) Adhesion
 GURUKUL STUDY CENTRE FOR TECHNICAL SERVICE EXAMINATION MECHANICAL ENGINEERING
GARIA STATION, KOLKATA- 84 PSC:- FLID MECHANICS 102
M- 9874074233, 7003482988, 8617277161 NAME- A
R- W- T-
Kaplan turbine is
(a) an inward flow reaction turbine (b) an axial flow reaction turbine
(c) an outward flow reaction turbine (d) a mixed flow reaction turbine
103. In a centrifugal pump, water enters the pump
(a) at the top (b) at the bottom (c) at the Centre (d) at none of the above
104. For a specific speed of 60 rpm to 300 rpm, the turbine preferred is:
(a) Peloton wheel (b) Francis turbine (c) Kaplan turbine (d) none of above
87.B 88.B 89.C 90.C 91.C 92.B 93.C 94.A 95.A
96.B 97.A 98.A 99.D 100.C 101.B 102.B 103.C 104.B
2000
105. The resultant upward pressure of the fluid on an immersed body is called
(a) Equilibrium (b) Buoyancy (c) Centre of pressure (d) None of the above
106. If the quantity of water flowing through flowing through a pipeline of 8 cm dia. is 0.1 m³/sec, velocity will be
(a) 80 m/sec (b) 40 m/sec (c) 20 m/sec (d) 10 m/sec
107. If the quantity of water flowing through flowing through a pipeline of 8 cm dia. is 0.1 m³/sec, velocity will be
(a) 80 m/sec (b) 40 m/sec (c) 20 m/sec (d) 10 m/sec
108. Centrifugal pump is used for its advantage over reciprocating pump due to
(a) Low initial cost and easy installation (b) Gross weight is considerable
(c) pulsating flow (d) None of the above
109. The first step in the of a centrifugal pump is
(A) Suction side water tank should be exposed to air
(B) priming, i.e., suction pipe and casing are filled with water.
(c) Delivery pipe should be filled up with water (d) None of the above
110. Deep well pump is a
(a) Low lift centrifugal pump (b) Vertical turbine pump (c) Horizontal turbine pump
(d) None of the above

111. In a vertical turbine pump electric motor is placed

(a) Below the pump (b) Much above the pump (c) In the same horizontal line
(d) None of the above

112. Submersible pump is a

(a) Multistage Vertical , turbine pump (b) Multistage horizontal turbine pump
(c) Single stage reciprocating pump (d) None of the above
113. The total pressure on an immersed surface inclined at an angle ( θ ) with free surface of liquid is
WA
(a) W A X Sinθ (b) W A X cosθ (c) W A X (d)
X
Where W = Sp. wt. of liquid, A = Area of immersed surface, X = Depth of the Centre of gravity of the immersed
surface from the liquid surface
114. A flow whose stream line is represented by a straight line is called-dimensional flow.
(a) one (b) Two (c) Three (d) Four
115. Venturimeter is used to measure
(a) The velocity of flowing liquid (b) The pressure of flowing liquid
(c) The discharge of liquid flowing in a pipe (d) None of the above
116. The total head of a liquid particle in motion is equal to
p v2 p v2 p v2 p v2
(a) + +z (b) − –z (c) + –z (d) − +z
w 2g w 2g w 2g w 2g
Where p = intensity of press. in N/m², V = velocity of liquid particle in m/sec., z= datum height in meter
117. The discharge over a rectangular notch is
(a) Inversely proportional to H (b) Directly proportional to H
(c) Directly proportional to H3/2 (d) Inversely proportional to Has
Where H Height of water above the apex of notch.
118. The hydraulic mean depth for a circular pipe of diameter (d) when running half-full is
(a) d (b) d/2 (c) d/4 (d) d/8
 GURUKUL STUDY CENTRE FOR TECHNICAL SERVICE EXAMINATION MECHANICAL ENGINEERING
GARIA STATION, KOLKATA- 84 PSC:- FLID MECHANICS 119
M- 9874074233, 7003482988, 8617277161 NAME- T
R- W- T-
he ratio of the inertia force to the viscous force is called
(a) Reynolds’s number (b) Mach number (c) Weber's number (d) Euler's number
120. In a reciprocating pump, the air vessels are used to
(a) Reduce the suction head (b) Reduce acceleration head (c) Increase delivery head
(d) Smoothen the flow
121. Theoretical power required to drive a reciprocating pump is
(a) WQ (HS + Hd) watt (b) WQ HS watt (c) WQ Hd watt (d) WQ (HS - Hd) watt
Where w = Sp. wt. in n/m², Q = Discharge in m/s, H S =suction head in meters
122. In order to avoid cavitation in a centrifugal pump
(a) Delivery pressure should be high (b) Suction pressure should be high
(c) Suction pressure should be low (d) Delivery pressure should be low
105.B 106.C 107.C 108.A 109.B 110.B 111.A 112.A 113.C
114.A 115.C 116.A 117.C 118. 119.A 120.B 121.A 122.B

1999
123. A differential manometer is used for
(A) measuring the difference off pressures between two points is a pipe/different pipes
(B)measuring small pressure
(c) accurately measuring the difference of low pressures (d) none of the above
124. The Centre of pressure of fully submerged uniformly thick plane lamina is always
(a) above the C.G of the lamina (b) below the C.G of the lamina
(c) at the C.G. of the lamina (d) none of the above
125. Continuity equation for incompressible fluid is
(a) P₁V₁ = P2V2 (b)A₁V₁ =A2V2 (c) P₁V₁ A₁=P2V2 (d) none of the above
126. The Bernoulli's theorem for liquid is applicable for
(a) Viscous fluids (b) compressible fluids (c) turbulent flow (d) none of the above
127. The relation between coefficient of discharge (Cd), co-efficient of velocity (C v) and coefficient of contraction (Cc) is
given by.
Cv
(a) Cd=Cv ×Cc (b) Cd=Cv=Cc (c) Cd = (d)Cv = Cd x Cd
Cc
128. The average value of coefficient discharge though an orifice is
(a) 0.60 (b) 0.52 (c) 0.62 (d) none of these
129. The loss of head at entrance in a pipe is equal to]
0.5 v 2 0.5 v 1.5 v2
(a) (b) (c) (d) 0.5 v2
2g g g
130. Reynolds’s number in case of a turbulent flow is
(a) less than 2000 (b) more than 2500 (c) more than 2800 (d) none of the above
131. Reciprocating pump - find their normal application, where it is required to developed a
(a) high head and high discharge (b) High head and low discharge
(c) low head and high discharge (d) low head and small discharge
132. Negative slip of a reciprocating p... happens when
(A) the suction pipe is long and delivery pipe is short
(B) the suction pipe is short and delivery pipe is long
(c) the pump is running at a low speeds (d) none of the above.
133. While starting the centrifugal pump
(a) delivery valve is kept wide upon (b) delivery valve is kept closed
(c) inlet valve is kept closed (d) delivery valve is opened slightly
134. Centrifugal pump requires
(a) more floor area and heavy foundation (b) less floor area and simple foundation
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(c) no priming (d) none of the above

135. The power developed by a hydraulic turbine is

(a) directly proportional to head off water (b) indirectly proportional to head of water
(c) equal to head of water (d) none of the above
136. The discharge of a vertical turbine pump is
(a) varies directly as the power (b) square root of the head (c) square of the diameter
(d) all of the above
137. In a submersible pump
(a) electric Motor is placed deep below the ground (b) electric motor is placed on the ground
(c) electric motor is placed mixt-way between ground and pump level (d) none of the above

138. Horse power capacity of the submersible pump is

(a) low (b) high (c) medium (d) all of them

123.A 124.B 125.B 126.D 127.A 128.C 129.A 130.C

131.B 132.A 133.B 134.B 135.A 136. 137.A 138.