1. The velocity corresponding to Reynold number of 2000 is called
Correct : C. Lower critical velocity
2. The loss of head at entrance in a pipe is (where v = Velocity of liquid in the pipe)
Correct : B. 0.5v²/2g
3. Which of the following is an example of laminar flow?
Correct : D. All of these
4. The discharge over a rectangular weir, considering the velocity of approach, is (whereH1 = H +
Ha = Total height of water above the weir, H = Height of water over the crest of the weir, and Ha = Height of water due to velocity of approach)
Correct : B. (2/3) Cd × L. √2g [H13/2 - Ha3/2]
5. The maximum efficiency of transmission through a pipe is
Correct : C. 66.67 %
6. The efficiency of power transmission through pipe is (where H = Total supply head, and hf = Head
lost due to friction in the pipe)
Correct : A. (H - hf )/H
7. The hydraulic mean depth or the hydraulic radius is the ratio of
Correct : A. Area of flow and wetted perimeter
8. The hydraulic mean depth for a circular pipe of diameter (d) is
Correct : B. d/4
9. A flow in which each liquid particle has a definite path, and the paths of individual particles do
not cross each other, is called
Correct : C. Streamline flow
10. The Reynold's number of a ship is __________ to its velocity and length.
Correct : A. Directly proportional
11. The velocity at which the laminar flow stops, is known as
Correct : B. Lower critical velocity
12. The velocity corresponding to Reynold number of 2800, is called
Correct : D. Higher critical velocity
13. The total energy of a liquid particle in motion is equal to
Correct : A. Pressure energy + kinetic energy + potential energy
14. When a cylindrical vessel containing liquid is revolved about its vertical axis at a constant
angular velocity, the pressure
Correct : A. Varies as the square of the radial distance
15. The length AB of a pipe ABC in which the liquid is flowing has diameter (d1) and is suddenly
contracted to diameter (d2) at B which is constant for the length BC. The loss of head due to sudden contraction, assuming coefficient of contraction as 0.62, is
Correct : D. 0.375 v₂²/2g
16. A large Reynold number is indication of
Correct : D. Highly turbulent flow
17. A tank of uniform cross-sectional area (A) containing liquid upto height (H1) has an orifice of
cross-sectional area (a) at its bottom. The time required to empty the tank completely will be
Correct : A. (2A√H₁)/(Cd × a√2g)
18. The total pressure on the top of a closed cylindrical vessel completely filled up with a liquid is
Correct : C. Directly proportional to (radius)4
19. For pipes, turbulent flow occurs when Reynolds number is
Correct : C. More than 4000
20. The discharge through a siphon spillway is
Correct : A. Cd × a × √(2gH)
21. The shear stress-strain graph for a Newtonian fluid is a
Correct : A. Straight line
22. When a cylindrical vessel of radius (r) containing liquid is revolved about its vertical axis ω rad/s,
then depth of parabola which the liquid assumes is
Correct : B. ω².r²/2g
23. The region between the separation streamline and the boundary surface of the solid body is
known as
Correct : A. Wake
24. The total pressure on the top of a closed cylindrical vessel of radius (r) completely filled up with
liquid of specific weight (w) and rotating at (ω) rad/s about its vertical axis, is
Correct : C. π w ω² r⁴/4g
25. The diameter of the nozzle (d) for maximum transmission of power is given by (where D =
Diameter of pipe, f = Darcy’s coefficient of friction for pipe, and l = Length of pipe)
Correct : C. d = (D⁵/8fl)1/4
26. The fluid forces considered in the Navier Stokes equation are
Correct : A. Gravity, pressure and viscous
27. Select the wrong statement
Correct : D. The diameter of an equivalent pipe is equal to that of a compound pipe
28. A flow through a long pipe at constant rate is called
Correct : A. Steady uniform flow
29. The velocity at which the flow changes from laminar flow to turbulent flow is called
Correct : A. Critical velocity
30. According to Darcy's formula, the loss of head due to friction in the pipe is (where f = Darcy's
coefficient, l = Length of pipe, v = Velocity of liquid in pipe, and d = Diameter of pipe)
Correct : D. 4flv²/2gd
31. The loss of head due to viscosity for laminar flow in pipes is (where d = Diameter of pipe, l =
Length of pipe, v = Velocity of the liquid in the pipe, μ = Viscosity of the liquid, and w = Specific weight of the flowing liquid)
Correct : D. 32μvl/wd²
32. The loss of pressure head in case of laminar flow is proportional to
Correct : A. Velocity
33. During the opening of a valve in a pipe line, the flow is
Correct : B. Unsteady
34. The main property that affects a boundary layer is__________
Correct : C. Viscosity
35. The layer that is influenced by a planetary boundary is called______
Correct : A. Atmospheric boundary layer
36. What is the other name for Stoke’s boundary layer?
Correct : C. Oscillatory boundary layer
37. Eddy viscosity is a turbulent transfer of_________
Correct : C. Momentum
38. The laminar boundary layer is a _________
Correct : A. Smooth flow
39. The turbulent boundary layer is a _________
Correct : A. Non-uniform with swirls
40. How do we measure the flow rate of liquid?
Correct : A. Coriolis method
41. How does a turbulent boundary layer produce swirls?
Correct : C. Due to eddies
42. Define Viscosity.
Correct : C. Resistance to flow of fluid
43. How can we determine whether the flow is laminar or turbulent?
Correct : A. Reynold’s number
44. The flow separation occurs when the fluid travels away from the __________
Correct : C. Adverse pressure gradient
45. The swirl caused due to eddies are called as ______
Correct : A. Vortices
46. Which among the following is a device that converts a laminar flow into a turbulent flow?
Correct : C. Turbulator
47. With the boundary layer separation, displacement thickness________
Correct : A. Increases
48. What is the instrument used for the automatic control scheme during the fluid flow?
Correct : D. Pilot Static Tube
49. What is D’Alembert’s Paradox?
Correct : B. Drag force= 0
50. The steady- state flow must satisfy ___________
Correct : A. Kirchhoff’s law
51. What is the name of the equation?
Q = (πΔPr4) / (8μL)
Correct : B. Poiseuille law
52. What is the name of the equation?
h = (fvL) / (2Dg)
Correct : A. Darcey equation
53. Which one of the following is a major loss?
Correct : A. frictional loss
54. Which property of the fluid accounts for the major losses in pipes?
Correct : C. viscosity
55. The frictional resistance for fluids in motion is
Correct : A. proportional to the velocity in laminar flow and to the square of the velocity in turbulent flow
56. The frictional resistance for fluids in motion is
Correct : B. independent of the pressure for both laminar and turbulent flows
57. The frictional resistance for fluids in motion is
Correct : D. proportional to the surface area of contact
58. The frictional resistance for fluids in motion varies
Correct : D. considerably with temperature for laminar flow and slightly with temperature for turbulent flow View Answer
59. Which one of the follflowing is correct?
Correct : D. the frictional resistance is independent of the nature of the surface area of contact for laminar flows but depends on the nature of the surface area of contact for turbulent flows View Answer
60. Which one of the follflowing is correct?
Correct : D. the frictional resistance is independent of the nature of the surface area of contact when the liquid flows at a velocity less than the critical velocity View Answer
61. Which one of the follflowing is correct?
Correct : C. Darcy-Weisbach’s formula is generally used for head loss in flow through both pipes and Chezy’s formula for open channels
62. A liquid flows through pipes 1 and 2 with the same flow velocity. If the ratio of their pipe diameters d1 : d2 be 3:2, what will be the ratio of the head loss in the two pipes?
Correct : C. 2:3
63. A liquid flowss through two similar pipes 1 and 2. If the ratio of their flow velocities v1 : v2 be 2:3, what will be the ratio of the head loss in the two pipes?
Correct : D. 4:9 View Answer
64. A liquid flows with the same velocity through two pipes 1 and 2 having the same diameter. If the length of the second pipe be twice that of the first pipe, what should be the ratio of the head loss in the two pipes?
Correct : A. 1:2
65. The head loss at the entrance of the pipe is that at it’s exit
Correct : B. half
66. On which of the factors does the co-efficent of bend in a pipe depend?
Correct : D. radius of curvature of the bend and pipe and angle of bend View Answer
67. The liquid flowing through a series of pipes can take up__________
Correct : A. Pipes of different diameters
68. What is the total loss developed in a series of pipes?
Correct : C. Sum of local losses plus the losses in each pipe
69. The total head loss for the system is equal to_________
Correct : D. Height difference of reservoirs View Answer
70. Which among the following is not a loss that is developed in the pipe?
Correct : D. Liquid velocity View Answer
71. Which among the following is the correct formula for head loss?
Correct : A. Z1-Z2
72. If the two reservoirs are kept at the same level, the head loss is _______
Correct : B. Zero
73. How do we determine the total discharge through parallel pipes?
Correct : A. Add them.
74. The pipe diameter is ________
Correct : B. Directly proportional to mass flow rate
75. Coefficient of friction of a laminar flow is_________
Correct : C. 16/Re
76. Shear stress in static fluid is
Correct : A. always zero
77. The specific weight of the fluid depends upon
Correct : B. mass density of the fluid
78. The rate of increase of velocity with respect to change in the position of fluid particle in a flow field is called as
Correct : C. convective acceleration
79. Minor losses occur due to
Correct : A. sudden enlargement in pipe
80. Kinematic eddy viscosity (ε) is the ratio of
Correct : D. eddy viscosity (η) to mass density (ρ)
81. The friction factor in fluid flowing through pipe depends upon
Correct : B. relative roughness of pipe surface
82. What is the effect of change in Reynold’s number on friction factor in turbulent flow?
Correct : A. As the Reynold’s number increases the friction factor increases in turbulent flow
83. The component of the total force exerted by fluid on a body in the direction parallel to the direction of motion is called as
Correct : A. lift
84. The sum of components of shear forces in the direction of flow of fluid is called as
Correct : A. shear drag
85. The liquid flowing through a series of pipes can take up__________
Correct : A. Pipes of different diameters
86. What is the total loss developed in a series of pipes?
Correct : C. Sum of local losses plus the losses in each pipe
87. The total head loss for the system is equal to_________
Correct : D. Height difference of reservoirs
88. Which among the following is not a loss that is developed in the pipe?
Correct : D. Liquid velocity
89. Which among the following is the correct formula for head loss?
Correct : A. Z1-Z2
90. If the two reservoirs are kept at the same level, the head loss is _______
Correct : B. Zero
91. How do we determine the total discharge through parallel pipes?
Correct : A. Add them.
92. The pipe diameter is ________
Correct : B. Directly proportional to mass flow rate
93. Coefficient of friction of a laminar flow is_________
Correct : C. 16/Re
94. Which among the following force is developed due to resistance of a fluid flow?
Correct : A. Viscous force
95. Which among the following force is developed due to resistance in its state of motion?
Correct : B. Inertial force
96. Which among the following is the correct formula for gravitational force?
Correct : A. F= Gm1m2/r2
97. Which among the following is present in pipe flow?
Correct : D. Pressure force
98. A force that is caused due to attraction of particles in the layer of fluid bulk is called?
Correct : C. Surface tension force
99. A force that is needed to bring back the body to its original position is called as?
Correct : C. Gravity force
100. The drag force acts in _____ to the flow velocity.