1. A floating body is said to be in a state of stable equilibrium
Correct : B. when the metacentre is above the centre of gravity
2. The increase in meta centric height
i) increases stability
ii) decreases stability
iii) increases comfort for passengers
iv) decreases comfort for passengers
The correct answer is
Correct : B. (i)and(iv)
3. A rectangular block 2 m long, 1 m wide and 1 m deep floats in water, the depth of immersion being 0.5 m. If water weighs 10 kN/m3, then the weight of the block is
Correct : B. lOkN
4. The point in the immersed body through which the resultant pressure of
the liquid may be taken to act is known as
Correct : C. center of pressure
5. If a vessel containing liquid moves downward with a constant acceleration
equal to ‘g’ then
Correct : A. the pressure throughout the liquid mass is atmospheric
6. When a liquid rotates at a constant angular velocity about a vertical axis
as a rigid body, the pressure intensity varies
Correct : B. as the square of the radial distance
7. An open cubical tank of 2 m side is filled with water. If the tank is rotated
with an acceleration such that half of the water spills out, then the acceleration is equal to
Correct : D. g
8. A right circular cylinder open at the top is filled with liquid and rotated about its vertical axis at such a speed that half the liquid spills out, then the pressure intensity at the center of bottom is
Correct : A. zero
9. The horizontal component of force on a curved surface is equal to the
Correct : B. force on a vertical projection of the curved surface
10. A closed tank containing water is moving in a horizontal direction along a straight line at a constant speed. The tank also contains a steel ball and a bubble of air. If the tank is decelerated horizontally, then
i) the ball will move to the front
ii) the bubble will move to the front
iii) the ball will move to the rear
iv) the bubble will move to the rear
Find out which of the above statements are correct ?
Correct : B. (i)and(iv)
11. The eddy viscosity for turbulent flow is
Correct : C. dependent on the flow
12. Flow at constant rate through a tapering pipe is
i) steady flow
ii) uniform flow
iii) unsteady flow
iv) non-uniform flow
The correct answer is
Correct : B. (i)and(iv)
13. In a two dimensional incompressible steady flow around an airfoil, the stream lines are 2 cm apart at a great distance from the airfoil, where the velocity is 30 m/sec. The velocity near the airfoil, where the stream lines are 1.5 cm apart, is
Correct : C. 40 m/sec.
14. When the velocity distribution is uniform over the cross-section, the
correction factor for momentum is
Correct : B. 1
15. Least possible value of correction factor for
i) kinetic energy is zero ii) kinetic energy is 1 iii) momentum is zero iv) momentum is 1 The correct statements are
Correct : D. (ii) and (iv)
16. If the velocity is zero over half of the cross-sectional area and is uniform over the remaining half, then the momentum correction factor is
Correct : C. 2
17. If velocity is zero over l/3rd of a cross-section and is uniform over remaining 2/3rd of the cross-section, then the correction factor for kinetic energy is
Correct : C. 9/4
18. The continuity equation pi V,A,= p2V2A2 is based on the following assumption regarding flow of fluid (where pi and p2 are mass densities.)
Correct : A. steady flow
19. Which of the following velocity potentials satisfies continuity equation ?
Correct : B. x2-y2
20. The motion of air mass in a tornado is a
Correct : D. forced vortex at center and free vortex outside
21. In a forced vortex motion, the velocity of flow is
Correct : A. directly proportional to its radial distance from axis of rotation
22. Stream lines and path lines always coincide in case of
Correct : A. steady flow
23. Equation of continuity is based on the principle of conservation of
Correct : A. mass
24. In steady flow of a fluid, the total accele ration of any fluid particle
Correct : A. can be zero
25. The pitot tube is used to measure
Correct : B. stagnation pressure
26. Hot wire anemometer is used to measure
Correct : B. velocity of gas
27. The theoretical value of coefficient of contraction of a sharp edged orifice
is
Correct : A. 0.611
28. Which of the following is used to measure the discharge ?
Correct : B. venturimeter
29. Select the incorrect statement.
Correct : C. Stream lines are parallel throughout the jet at vena contracta.
30. Size of a venturimeter is specified by
Correct : A. pipe diameter
31. Due to each end contraction, the discharge of rectangular sharp crested
weir is reduced by
Correct : A. 5%
32. The discharge through a V- notch varies as
Correct : C. H5/2
33. Which of the following is an incorrect statement ?
Correct : D. None of the above statement is correct.
34. Coefficient of velocity of venturimeter
Correct : C. is equal to the coefficient of discharge of venturimeter
35. The pressure at the summit of a syphon is
Correct : B. less than atmospheric
36. Ay between two stream lines represents
Correct : B. discharge
37. Coefficient of velocity for Borda’s mouth piece running full is
Correct : B. 0.707
38. Coefficient of discharge for a totally submerged orifice as compared to
that for an orifice discharging free is
Correct : A. slightly less
39. The major loss of energy in long pipes is due to
Correct : D. friction
40. Coefficient of contraction for an external cylindrical mouthpiece is
Correct : A. 1.00
41. Which of the following has highest coefficient of discharge ?
Correct : B. venturimeter
42. In a Sutro weir, the discharge is proportional to (where H is head.)
Correct : D. H
43. The discharge over a broad crested weir is maximum when the depth of (where H is the available head.)
flow is
Correct : D. 2 H/3
44. Which of the following statements is correct?
Correct : A. Lower critical Reynolds number is of no practical significance in pipe flow problems.
45. For a sphere of radius 15 cm moving with a uniform velocity of 2 m/sec
through a liquid of specific gravity 0.9 and dynamic viscosity 0.8 poise, the Reynolds number will be
Correct : D. 675
46. The shear stress distribution for a fluid flowing in between the parallel
plates, both at rest, is
Correct : C. zero at the mid plane and varies linearly with distance from mid plane
47. If x is the distance from leading edge, then the boundary layer thickness in
laminar flow varies as
Correct : A. x
48. Stanton diagram is a
Correct : A. log-log plot of friction factor against Reynolds number
49. The depth ‘d’ below the free surface at which the point velocity is equal to
the average velocity of flow for a uniform laminar flow with a free surface, will be (where D is the depth of flow.)
Correct : B. 0.577 D
50. The boundary layer thickness in turbulent flow varies as (where x is the distance from leading edge.)
Correct : C. x4/5
51. The distance y from pipe boundary, at which the point velocity is equal to
average velocity for turbulent flow, is (where R is radius of pipe.)
Correct : A. 0.223 R
52. If a sphere of diameter 1 cm falls in castor oil of kinematic viscosity 10
stokes, with a terminal velocity of 1.5 cm/sec, the coefficient of drag on the sphere is
Correct : C. 160
53. In case of an airfoil, the separation of flow occurs
Correct : A. at the extreme rear of body
54. When an ideal fluid flows past a sphere,
Correct : D. total drag is zero
55. With the same cross-sectional area and immersed in same turbulent flow,
the largest total drag will be on
Correct : A. a circular disc of plate held normal to flow
56. In which of the following the friction drag is generally larger than
pressure drag?
Correct : D. an airfoil
57. For hydro-dynamically smooth boundary, the friction coefficient for
turbulent flow is
Correct : B. dependent only on Reynolds number
58. The value of friction factor ‘f’ for smooth pipes for Reynolds number 106
is approximately equal to
Correct : B. 0.01
59. For laminar flow in a pipe of circular cross-section, the Darcy’s friction
factor f is
Correct : C. inversely proportional to Reynolds number and indpendent of pipe wall roughness
60. Separation of flow occurs when
Correct : C. the boundary layer comes to rest
61. The ratio of average velocity to maximum velocity for steady laminar flow
in circular pipes is
Correct : A. 1/2
62. The distance from pipe boundary, at which the turbulent shear stress is
one-third die wall shear stress, is (where R is the radius of pipe.)
Correct : A. 1/3 R
63. The discharge of a liquid of kinematic viscosity 4 cm2/sec through a 8 cm
dia-meter pipe is 3200n cm7sec. The type of flow expected is
Correct : A. laminar flow
64. The Prartdtl mixing length is
Correct : A. zero at the pipe wall
65. The velocity distribution for laminar flow through a circular tube
Correct : C. varies parabolically with maximum at the centre
66. A fluid of kinematic viscosity 0.4 cm2/sec flows through a 8 cm diameter
pipe. The maximum velocity for laminar flow will be
Correct : B. 1 m/sec
67. The losses are more in
Correct : C. turbulent flow
68. The wake
Correct : B. always occurs after a separation point
69. The maximum thickness of boundary layer in a pipe of radius r is
Correct : C. r
70. The hydraulic grade line is
Correct : B. never above the energy grade line
71. Two pipe systems are said to be equivalent when
Correct : A. head loss and discharge are same in two systems
72. In series-pipe problems
Correct : B. the discharge is same through each pipe
73. Select the correct statement.
Correct : D. The absolute roughness increases with time.
74. A valve is suddenly closed in a water main in wl.ich the velocity is 1 m/sec and velocity of pressure wave is 981 m/ sec. The inertia head at the valve will be
Correct : C. 100m
75. The speed of a pressure wave through a pipe depends upon
Correct : C. the bulk modulus for the fluid
76. When time of closure tc = L/v0 (where L is length of pipe and v0 is speed
of pressure wave), the portion of pipe length subjected to maximum head is
Correct : A. L/4
77. If the elevation of hydraulic grade line at the junction of three pipes is above the elevation of reservoirs B and C and below reservoir A, then the direction of flow will be
Correct : C. from reservoir C to reservoirs A and B
78. The length of a pipe is 1 km and its diameter is 20 cm. If the diameter of
an equivalent pipe is 40 cm, then its length is
Correct : A. 32 km
79. Two pipes of same length and diameters d and 2d respectively are connected in series. The diameter of an equivalent pipe of same length is
Correct : A. less than d
80. The horse power transmitted through a pipe is maximum when the ratio
of loss of head due to friction and total head supplied is
Correct : A. 1/3
81. The boundary layer thickness at a distance of l m from the leading edge of a flat plate, kept at zero angle of incidence to the flow direction, is O.l cm. The velocity outside the boundary layer is 25 ml sec. The boundary layer thickness at a distance of 4 m is (Assume that boundary layer is entirely laminar.)
Correct : B. 0.20 cm
82. Drag force is a function of
i) projected area of the body
ii) mass density of the fluid
iii) velocity of the body
The correct answer is
Correct : D. (i), (ii) and (iii)
83. The correct relationship among displacement thickness d, momentum
thickness m and energy thickness e is
Correct : D. e > d > m
84. For laminar flow in circular pipes, the Darcy’s friction factor f is equal to
Correct : C. 64/ Re
85. Surge wave in a rectangular channel is an example of
i) steady flow ii) unsteady flow iii) uniform flow iv) non-uniform flow
The correct answer is