Free Solved objective Questions on Fluid Mechanics

Free Solved objective Questions on Fluid Mechanics

1. A fluid is a substance that
(a) Always expands until it fills any container
(b) Has the same shear stress at a point
regardless of its motion
(c) Cannot remain at rest under action of any
shear force
(d) Cannot be subjected to shear forces
ANSWER: (b)

2. Length of mercury column at a place at an
altitude will vary with respect to that at ground
in a
(a) Linear relation
(b) hyperbolic relation
(c) Parabolic relation.
(d) Manner first slowly and then steeply
ANSWER: (d)

3. When power is transmitted through a considerable distance by means of water under
pressure, the maximum power is transmitted when frictional loss of head is
(a) One third of the total head supplied
(b) Half of the total head supplied
(c) 10% of the total head
(d) 17.7% 0f the total head.
ANSWER: (a)

4. A rotameter is a device used to measure
(a) Velocity of fluid in pipes
(b) Velocity of gauges
(c) Votex flow
(d) Flow of fluids
ANSWER: (d)

5. The continuity equation
(a) Expresses relationship between hydraulic
parameters of flow
(b) Expresses the relationship, between work and
energy
(c) Is based on Bernoulli’s theorem
(d) Relates the mass rate of flow along a stream
line.
ANSWER: (d)

6. Of the following, dimensionless parameter is
(a) Pressure coefficient
(b) Froude number
(c) Darcy Weisbach friction factor
(d) All of the above
ANSWER: (d)

7. One dimensional flow
(a) Restricted to flow in a straight line
(b) Neglects changes in a transverse direction
(c) Steady uniform flow
(d) A uniform flow
ANSWER: (b)

8. Steady flow occurs when
(a) Pressure does not change along the flow
(b) Velocity does not change
(c) Conditions change gradually with time
(d) Conditions do not change with time at any point.
ANSWER: (d)

9. Equation Continuity of fluids is applicable only when the flow is
(a) Steady
(b) One dimensional
(c) Compressive
(d) All of the above
ANSWER: (d)

10. If the particles of a fluid attain such velocities that vary from point to point in magnitude and
direction as well as from instant, the flow is
(a) Uniform flow
(b) Steady flow
(c) Turbulent flow
(d) Laminer flow
ANSWER: (c)

11. In a turbulent flow in a pipe
(a) Reynolds number is greater than 10000
(b) Fluid particles move in straight lines
(c) Head loss varies linearly with flow rate
(d) Shear stress varies linearly with radius
ANSWER: (d)

12. In laminar flow, maximum velocity at the centre
Of pipe is how many times to the average velocity
(a) Two
(b) Three
(c) Four
(d) None of the above
ANSWER: (a)

13. A sharp edged obstruction over which the flow
of a fluid takes place is
(a) Wear
(b) Notch
(c) Orifice
(d) None of these
ANSWER: (c)

14. The non-dimensional factor governing frictional resistance is
(a) Reynolds number
(b) Weber number
(c) Froude number
(d) Mach number
ANSWER: (d)

15. Non uniform flow occurs when
(a) Direction and magnitude of velocity at all
points are identical
(b) Velocity of successive fluid particles, at any
point, is same at successive periods of time
(c) Magnitude and direction of velocity do not
change from point to point in the fluid
(d) Velocity, depth, pressure, etc. changes point
to point in the fluid flow
ANSWER: (d)

16. 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
ANSWER: (d)

17. The fluid forces considered in the Navier Stokes
equation are
(a) Gravity, pressure and viscous
(b) Gravity, pressure and turbulent
(c) Pressure, viscous and turbulent
(d) Gravity, viscous and turbulent
ANSWER: (a)

18. Reynolds number is significant in
(a) Supersonics, as with projectile and jet propulsion
(b) Full immersion or completely enclosed flow,as with pipes, aircraft wings, nozzles etc.
(c) Simultaneous motion through two fluids where there is a surface of discontinuity,
gravity forces, and wave making effect, as with ship’s hulls
(d) All of the above
ANSWER: (b)

Q.51. A streamline is defined as the line
(a) Parallel to central axis flow
(b) Parallel to outer surface to pipe g
(c) Of equal velocity in a flow
(d) Along which the pressure drop is uniform
ANSWER: (c)

19. The cepoletti weir functions as if it were a
following notch without end contractions
(a) Triangular notch
(b) Trapezoidal notch
(c) Rectangular notch
(d) Parallelogram notch
ANSWER: (c)

20.Match number is significant in
(a) Supersonics, as with projectiles and jet
propulsion
(b) Full immersion or completely enclosed flow,
as with pipes, aircrafts wings, nozzles etc.
(c) Simultaneous motion through two fluids
where there is a surface of discontinuity
gravity force, and wave making effects, as
with ship’s hull
(d) All of the above
ANSWER: (a)