300+ TOP FLUID MECHANICS Interview Questions

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

56. The discharge over a broad crested weir is maximum when the depth of flow is
a) H/3
b) H/2
c) 2 H/5
d) 2 H/3
where H is the available head.
Ans: d
57. Which of the following statements is correct?
a) Lower critical Reynolds number is of no practical significance in pipe flow problems.
b) Upper critical Reynolds number is significant in pipe flow problems.
c) Lower critical Reynolds number has the value 2000 in pipe flow
d) Upper critical Reynolds number is the number at which turbulent flow changes to laminar flow.
Ans: a
58. 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
a) 300
b) 337.5
c) 600
d) 675
Ans: d
59. The shear stress distribution for a fluid flowing in between the parallel plates, both at rest, is
a) constant over the cross section
b) parabolic distribution across the section
c) zero at the mid plane and varies linearly with distance from mid plane
d) zero at plates and increases linearly to midpoint
Ans: c
60. If x is the distance from leading edge, then the boundary layer thickness in laminar flow varies as
a) x
b) x
c) x
d) x/7
Ans: a

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

a) zero
b) one-fourth its value when cylinder was full
c) one-half its value when cylinder was full
d) cannot be predicted from the given data
Ans: a

FLUID MECHANICS Interview Questions and Answers

100 TOP FLUID MECHANICS Interview Questions<—– CLICK HERE

61. Stanton diagram is a
a) log-log plot of friction factor against Reynolds number
b) log-log plot of relative roughness against Reynolds number
c) semi-log plot of friction factor against Reynolds number
d) semi-log plot of friction factor against relative roughness
Ans: a
62. 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
a) 0.423 D
b) 0.577 D
c) 0.223 D
d) 0.707 D
where D is the depth of flow.
Ans: b
63. The boundary layer thickness in turbulent flow varies as
a) x”7
b) x,/2
c) x4/5
d) x3/5
where x is the distance from leading edge.
Ans: c
64. The distance y from pipe boundary, at which the point velocity is equal to average velocity for turbulent flow, is
a) 0.223 R
b) 0.423 R
c) 0.577 R
d) 0.707 R
where R is radius of pipe.
Ans: a
65. 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
a) less than 1
b) between 1 and 100
c) 160
d) 200
Ans: c