Free Fluid Flow Operations MCQs with Answers
909 Fluid Flow Operations MCQs from Chemical Engineering, each with the correct answer and a written explanation of why it is correct. Free and unlimited, with no account needed.
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909 questions · page 20 of 46
- A. 10
- B. 100
- C. 1000
- D. 10000
Explanation: The ram-to-plunger area ratio is (10/1)^2 = 100. A 10-ton load equals 10,000 kgf, so the plunger force is 10,000/100 = 100 kgf.
Correct answer: 100- A. 1
- B. > 3
- C. 50
- D. < 0.3
Explanation: Gas compressibility effects are usually negligible when the Mach number is below about 0.3, because pressure disturbances travel much…
Correct answer: < 0.3- A. High capacity at low heads
- B. High capacity at high heads
- C. Low capacity at high heads
- D. Low capacity at low heads
Explanation: Propeller pumps are axial-flow machines designed to move a large volume of liquid against a relatively small head.
Correct answer: High capacity at low heads- A. Two
- B. Three
- C. Four
- D. Eight
Explanation: The hydraulic diameter is defined as D_h = 4A/P, where A is the flow area and P is the wetted perimeter.
Correct answer: Four- A. Shear stress to gravitational stress
- B. Drag stress to shear stress
- C. Inertial stress to shear stress
- D. Inertial stress to gravitational stress
Explanation: The Froude number compares inertial effects with gravitational effects, commonly written as Fr = V/√(gL).
Correct answer: Inertial stress to gravitational stress- A. Fixed in space in steady flow
- B. Always the path of particle
- C. Drawn normal to the velocity vector at every point
- D. A line connecting the mid points of flow cross-section
Explanation: In steady flow, the velocity field does not change with time, so streamlines remain fixed in space.
Correct answer: Fixed in space in steady flow- A. Single stage centrifugal pump
- B. Duplex/triplex reciprocating pump
- C. Screw pump
- D. Gear pump
Explanation: Duplex or triplex reciprocating pumps are positive-displacement pumps capable of delivering crude oil from wells against substantial…
Correct answer: Duplex/triplex reciprocating pump- A. Viscosity of the liquid
- B. Depth of immersion of the body
- C. Weight of the liquid displaced
- D. Surface tension of the liquid
Explanation: Archimedes’ principle states that buoyant force equals the weight of the liquid displaced by the submerged portion of the body.
Correct answer: Weight of the liquid displaced- A. Specific gravity of the liquid
- B. Suction lift
- C. Discharge head
- D. All A., B. and C.
Explanation: For a given flow rate, pump power is proportional to specific gravity multiplied by the total head.
Correct answer: All A., B. and C.- A. Brings about no further reduction of
- B. Increases
- C. Decreases
- D. None of these
Explanation: Once a pipe is hydraulically smooth, the roughness elements are buried within the viscous sublayer, so reducing roughness further does not…
Correct answer: Brings about no further reduction of- A. ft-lb/sec
- B. ft-lb/ft3
- C. ft-lbf/lb
- D. ft-lbf/sec
Explanation: Velocity head is v²/2g, which has the dimensions of length. In British engineering units, ft-lbf/lb reduces to ft, so option c is correct.
Correct answer: ft-lbf/lb- A. Fluid characteristics
- B. Particle size
- C. Neither A. nor B.
- D. Both A. and B.
Explanation: Fluidised-bed behaviour is governed by both the fluid properties, such as density and viscosity, and particle characteristics, especially…
Correct answer: Both A. and B.- A. M2/sec
- B. N/m2. sec
- C. Kg. sec/m
- D. None of these
Explanation: Kinematic viscosity is dynamic viscosity divided by density, giving SI units of m²/s.
Correct answer: M2/sec- A. 39.6y
- B. 48y
- C. 49.2y
- D. 58y
Explanation: The centroid is 5 ft below the oil surface because the 4-ft inclined length has a vertical rise of 2 ft from its lower edge at 6 ft depth.
Correct answer: 48y- A. 64/NRe,P
- B. 16/NRe,P
- C. 24/NRe,P
- D. 48/NRe,P
Explanation: For spherical particles in the Stokes-law range, the drag coefficient varies inversely with particle Reynolds number and is given by C_D =…
Correct answer: 24/NRe,P- A. Speed of
- B. Diameter of
- C. All A., B. and C.
- D. Fluid velocity leaving
Explanation: The theoretical centrifugal-pump head follows Euler’s pump equation and depends on impeller speed, impeller diameter, and the velocity…
Correct answer: All A., B. and C.- A. Pressure drop increases linearly
- B. None of these
- C. Area through which fluid flows does not vary
- D. Pressure drop is almost constant
Explanation: A rotameter operates at an approximately constant pressure drop, while the float rises to increase the annular flow area as flow rate…
Correct answer: Pressure drop is almost constant- A. The porosity of the bed when true fluidisation begins
- B. That corresponding to completely fluidised bed
- C. That corresponding to static bed
- D. Less than that of the' static bed
Explanation: The minimum fluidisation porosity is the bed voidage at the instant fluidisation begins, when the upward fluid force just supports the bed…
Correct answer: The porosity of the bed when true fluidisation begins- A. Wall roughness
- B. Both A. & B.
- C. Reynolds number
- D. Neither A. nor B.
Explanation: For turbulent flow, frictional pressure loss depends on both Reynolds number and wall roughness through the friction factor.
Correct answer: Both A. & B.- A. Sump
- B. Volute
- C. Vacuum
- D. Submerged
Explanation: A vacuum pump draws gas from a pressure below atmospheric and discharges it at or near atmospheric pressure.
Correct answer: Vacuum