# Fluid Mechanics 5

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

Subject:  Fluid Mechanics Paper 5

Part 5: List for questions and answers of Fluid Mechanics I

Q1. A pitot tube is used to measure
a) Pressure
b) Difference in pressure
c) Velocity of flow
d) None of these

Q2. The continuity equation of fluid mechanics utilises the principle of conservation of
a) Momentum
b) Mass
c) Energy
d) Both (b) and (c)

Q3. A floating/submerged body is always stable, if its centre of gravity
a) Lies above its centre of buoyancy
b) And centre of buoyancy coincide
c) Lies below its centre of buoyancy
d) Lies above its meta centre

Q4. The co-efficient of discharge of an orifice meter is a function of
a) Reynolds number at the orifice
b) Ratio of orifice dia to pipe dia
c) Both (a) and (b)
d) None of the above parameters, and has a constant value of 0.61

Q5. Critical velocity in a pipe flow
a) Increases as fluid viscosity increases
b) Increases as pipe diameter increases
a. Independent of fluid density
b. None of these

Q6. In an incompressible flow of fluid, the fluid
a) Temperature remains constant
b) Compressibility is greater than zero
c) Density does not change with pressure and temperature.
d) Is frictionless

Q7. The fluid property, due to which, mercury does not wet the glass is
a) Surface tension
b) Viscosity
c) Cohesion

Q8. Laminar flow of a Newtonian fluid ceases to exist, when the Reynolds number exceeds
a) 4000
b) 2100
c) 1500
d) 3000

Q9. The velocity profile for turbulent flow through a closed conduit is
a) Logarithmic
b) Parabolic
c) Hyperbolic
d) Linear

Q10. Power loss in an orifice meter is __________ that in a venturimeter
a) Less than
b) Same as
c) More than
d) Data insufficient, cannot be predicted

Q11.What is the normal range of exit cone angle of a venturimeter?
a) 2 to 5
b) 7 to 15
c) 15 to 25
d) Greater than 25

Q12.The Stoke’s stream function applies to theb
a) Irrotational flow only
b) Ideal/non-viscous fluids only
c) Cases of axial symmetry
d) None of these

Q13. The simple pitot tube measures the __________ pressure.
a) Static
b) Dynamic
c) Total
d) None of these

Q14. Manometers measure the __________ pressure
a) Vacuum as well as the atmospheric
b) Difference in
c) Absolute
d) Gage

Q15. Bernoulli’s equation is dependent on the
a) First law of thermodynamics
b) Third law of thermodynamics
c) Law of conservation of momentum
d) None of these

Q16. The simple pitot tube does not measure the
a) Static pressure
b) Dynamic pressure
c) Velocity at the stagnation point
d) All (a), (b) and (c)

Q17. Isotropic turbulence occurs
a) Where there is no velocity gradient
b) At higher temperatures
c) Only in Newtonian fluids
d) None of these

Q18. Euler’s equation of motion states, that at every point, the
a) Fluid momentum is constant
b) Force per unit mass equals acceleration
c) Rate of mass outflow is equal to the rate of mass inflow
d) None of these

Q19. The Navier-Stokes equation deals with the law of conservation of
a) Mass
b) Energy
c) Both (a) and (b)
d) Momentum

Q20. During ageing of fluid carrying pipes, the
a) Pipe becomes smoother with use
b) Friction factor increases linearly with time
c) Absolute roughness decreases with time
d) Absolute roughness increases linearly with time

Part 5: List for questions and answers of Fluid Mechanics I