Category: FLUID MECHANICS Questions

100 TOP FLUID MECHANICS Interview Questions pdf<—–CLICK HERE

66. In case of an airfoil, the separation of flow occurs
a) at the extreme rear of body
b) at the extreme front of body
c) midway between rear and front of body
d) any where between rear and front of body depending upon Reynolds number
Ans: a
67. When an ideal fluid flows past a sphere,
a) highest intensity of pressure occurs around the circumference at right angles to flow
b) lowest pressure intensity occurs at front stagnation point
c) lowest pressure intensity occurs at rear stagnation point
d) total drag is zero
Ans: d
68. With the same cross-sectional area and immersed in same turbulent flow, the largest total drag will be on
a) a circular disc of plate held normal to flow
b) a sphere
c) a cylinder
d) a streamlined body
Ans: a
69. In which of the following the friction drag is generally larger than pressure drag?
a) a circular disc or plate held normal to flow
b) a sphere
c) a cylinder
d) an airfoil
Ans: d
70. For hydro-dynamically smooth boundary, the friction coefficient for turbulent flow is
a) constant
b) dependent only on Reynolds number
c) a function of Reynolds number and relative roughness
d) dependent on relative roughness only
Ans: b

a) 4 kN/m2
b) 10 kN/m2
c) 12 kN/m2
d) 14 kN/m2
Ans: d

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 ?
a) (i) and (ii)
b) (i)and(iv)
c) (ii) and (iii)
d) (iii) and (iv)
Ans: b

a) discharge
b) velocity of gas
c) pressure intensity of gas
d) pressure intensity of liquid
Ans: b

100 TOP FLUID MECHANICS Interview Questions and Answers <—-CLICK HERE

71. The value of friction factor ‘f’ for smooth pipes for Reynolds number 106 is approximately equal to
a) 0.1
b) 0.01
c) 0.001
d) 0.0001
Ans: b
72. For laminar flow in a pipe of circular cross-section, the Darcy’s friction factor f is
a) directly proportional to Reynolds number and independent of pipe wall roughness
b) directly proportional to pipe wall roughness and independent of Reynolds number
c) inversely proportional to Reynolds number and indpendent of pipe wall roughness
d) inversely proportional to Reynolds number and directly proportional to pipe wall roughness
Ans: c
73. Separation of flow occurs when
a) the pressure intensity reaches a minimum
b) the cross-section of a channel is reduced
c) the boundary layer comes to rest
d) all of the above
Ans: c
74. The ratio of average velocity to maximum velocity for steady laminar flow in circular pipes is
a) 1/2
b) 2/3
c) 3/2
d) 2
Ans: a
75. The distance from pipe boundary, at which the turbulent shear stress is one-third die wall shear stress, is
a) 1/3 R
b) 1/2 R
c) 2/3 R
d) 3/4R
where R is the radius of pipe.
Ans: a

a) at the centroid of the submerged area
b) always above the centroid of the area
c) always below the centroid of the area
d) none of the above
Ans: c