Free Fluid Flow Operations MCQs with Answers

• A. Elastic
• B. Tensile
• C. Vibratory
• D. Centrifugal

Explanation: Ordinary fluids cannot sustain tensile stress, because they separate or cavitate instead of carrying a pulling force.

• A. 4fB
• B. fB/2
• C. fB/4
• D. 2fB

Explanation: The Blasius factor is commonly given as the Darcy or Darcy-Weisbach friction factor, whereas the Fanning factor is one-fourth of it.

• A. 1500
• B. 330
• C. 1000
• D. 3000

Explanation: Sound travels through ordinary water at approximately 1500 m/s at room temperature.

• A. None of these
• B. Closed
• C. Either open or closed
• D. Open

Explanation: An axial-flow pump should be started with its delivery valve open because it develops high flow and relatively low head, so throttling the…

• A. Stream
• B. Path
• C. Equipotential
• D. None of these

Explanation: A pathline is the actual trajectory traced by one particular fluid particle as it moves with time.

• A. Piston
• B. Positive displacement
• C. Gear
• D. Sump

Explanation: Gear pumps are positive-displacement pumps that can be manufactured with corrosion-resistant plastics and other special materials.

• A. μ
• B. 1/√μ
• C. √μ
• D. 1/μ

Explanation: For laminar flow in a circular pipe, Hagen–Poiseuille’s relation gives velocity proportional to the pressure gradient divided by…

• A. Venturimeter
• B. Orificemeter
• C. Flow-nozzle
• D. Δp is same for all

Explanation: A venturimeter has gradual converging and diverging sections, so it causes the smallest permanent pressure loss for a given flow rate.

• A. Dilatants
• B. Pseudo plastic
• C. Newtonian
• D. Bingham plastic

Explanation: Rubber latex is shear-thinning: its apparent viscosity decreases as the shear rate increases, which characterizes a pseudoplastic fluid.

• A. Solids
• B. Liquids
• C. Slurries
• D. Fluids

Explanation: Diaphragm pumps are especially useful for slurries because the flexible diaphragm and valves can handle suspended solids while isolating…

• A. Equivalent
• B. None of these
• C. Prandtl mixing
• D. Transition

Explanation: The entrance or transition length is the distance required for the developing boundary layers to meet at the pipe centre and produce a…

• A. Sump
• B. Hyster
• C. Mono
• D. Submerged

Explanation: A Hyster pump is classified among vacuum pumps, used to produce low pressures by removing gas from a system.

• A. Long pipe at constant rate
• B. Long pipe at decreasing rate
• C. Expanding tube at constant rate
• D. Expanding tube at increasing rate

Explanation: Steady flow has no variation with time, while non-uniform flow varies from place to place.

• A. 5 kg/m3
• B. 0 N/m
• C. 1 N
• D. ∞ N/m2

Explanation: Bulk modulus measures resistance to volume compression, K = -V(dp/dV). An incompressible fluid has zero volume change for any finite…

• A. Kozeny-Carman
• B. Blake-Plummer
• C. Leva's
• D. Fanning friction factor

Explanation: The Kozeny-Carman equation relates pressure drop through a packed bed to particle size, void fraction, viscosity and flow rate…

• A. Centre of gravity of a submerged body
• B. Centroid of the displaced volume of fluid
• C. Centroid of the volume of any floating body
• D. None of these

Explanation: Buoyant force acts through the centre of buoyancy, which is the centroid of the displaced fluid volume.

• A. Various momentums
• B. Various masses
• C. Different forms of mechanical energy
• D. None of these

Explanation: Bernoulli's equation expresses conservation of mechanical energy by relating pressure energy, kinetic energy and potential elevation…

• A. For which shear & deformation are related as T = μ (∂u/∂y)
• B. Which needs a minimum shear, before it starts deforming
• C. Which follows Newton's law of motion
• D. None of these

Explanation: A Newtonian fluid has shear stress directly proportional to the velocity gradient, τ = μ(∂u/∂y), with constant viscosity at fixed…

• A. 0.5
• B. 2
• C. 4
• D. 1

Explanation: For geometrically similar centrifugal-pump operation, power varies with the cube of speed, P ∝ N³.

• A. Inertial stress to drag stress
• B. Drag stress to inertial stress
• C. Inertial stress to gravitational stress
• D. Gravitational stress to drag stress

Explanation: The power number compares the power or drag effect required for agitation with the inertial effect, and is written as Np = P/(ρN³D⁵).