# Fluid Mechanics 4

Civil Engineering MCQ. PWD, CPWD, RRB, SSC, Mock Test Paper

Subject:  Fluid Mechanics Paper 4

Part 4: List for questions and answers of Fluid Mechanics I

Q1. Centre of buoyancy is
a) Centroid of the floating body
b) Centroid of the fluid displaced
c) Centre of pressure of the displaced liquid
d) None of these.

Q2. Total energy line is
d) All the above

Q3. A body of dimensions 1.5 m x 1.0 m x 2 m weighs 3000 kg in water. Its specific gravity is
a) 0.8
b) 0.9
c) 1.0
d) 1.1

Q4. An orifice is called a large orifice if water head, is
a) Twice the diameter of the orifice
b) Thrice the diameter of the orifice
c) Four times the diameter of the orifice
d) Five times the diameter of the orifice

Q5. For the two dimensional flow, the stream function is given by ψ = 2xy. The velocity at a point (3, 4) is
a) 6 m/sec
b) 8 m/sec
c) 10 m/sec
d) 12 m/sec

Q6. A floating body attains stable equilibrium if its metacentre is
a) At the centroid
b) Above the centroid
c) Below the centroid
d) Anywhere

Q7. Atmospheric pressure varies with
a) Altitude
b) Temperature
c) Weather conditions
d) All of the above

Q8.If velocities of fluid particles vary from point to point in magnitude and direction, as well as from instant to instant, the flow is said to be
a) Laminar
b) Turbulent flow
c) Uniform flow
d) Non-uniform flow

Q9. The following is not a laminar flow
a) Flow of oil in measuring instruments
b) Flow in beds in ground water
c) Rise of water in plants through roots
d) Flow in water pipe lines.

Q10. Molecules of fluids get attracted due to
a) Capillarity action
b) Surface tension
d) Cohesion

Q11. Atmospheric pressure is equal to water column head of
a) 9.81 m
b) 5.0 m
c) 10.30 m
d) 7.5 m

Q12.Piezometers is used to measure
a) Pressure in water channels, pipes etc
b) Difference in pressure at two points
c) Atmospheric pressure
d) Very low pressure.

Q13. Manometers are used to measure
a) Pressure in water channels, pipes etc
b) Difference in pressure at two points
c) Atmospheric pressure
d) Very low pressure

Q14. Flow in pipes is turbulent if Reynolds number is
a) Less than 2100
b) More than 3000
c) Between 2100 and 3000
d) None of these

Q15. The Bernoulli’s equation is based on the assumption that
a) There is no loss of energy of the liquid flowing
b) The velocity of flow is uniform across any cross-section of the pipe
c) No force except gravity acts on the fluid
d) All of the above

Q16. When the flow parameters at any given instant remain same at every point, then flow is said to be
a) Quasi-static
c) Laminar
d) Uniform

Q17. In flowing liquids pitot tubes are used measure
a) Discharge
b) Pressure
c) Velocity
d) Depth

Q18. Orifice-meter is used to measure
a) Pressure at the point
b) Discharge
c) Average speed
d) Velocity

Q19. Water belongs to
a) Newtonian fluids
b) Non-Newtonian fluids
c) Compressible fluid
d) None of these.

Q20. The flow is called rotational if its velocity normal to the plane of area is equal to
a) Angular velocity vector
b) Twice the angular velocity vector
c) Thrice the angular velocity vector
d) None of these

Part 4: List for questions and answers of Fluid Mechanics I