All Free Chemical Engineering MCQs with Answers
Every Chemical Engineering question in the bank, across all chapters, each with the correct answer and a written explanation. Free and unlimited, with no account needed.
6,983 questions · page 210 of 350
- A. Normal
- B. Convective
- C. Local
- D. Tangential
Explanation: The local acceleration is caused by the time variation of velocity at a fixed position, so it represents the unsteady nature of flow.
Correct answer: Local- A. Cv . Va
- B. Cc . √(2gH)
- C. Cd . √(2gH)
- D. Cv . √(2gH)
Explanation: At the vena contracta, the actual velocity equals the ideal theoretical velocity multiplied by the coefficient of velocity, giving…
Correct answer: Cv . √(2gH)- A. Manometer
- B. Pitot tube
- C. Rotameter
- D. None of these
Explanation: A Pitot tube is suitable for high-velocity gas streams because it measures the stagnation pressure and hence the local velocity from the…
Correct answer: Pitot tube- A. Having high viscosities
- B. Moving at low velocities
- C. Both A. & B.
- D. Neither A. nor B.
Explanation: For high-viscosity fluids or very low velocities, viscous effects spread well beyond a thin boundary layer and can influence the entire…
Correct answer: Both A. & B.- A. None of these
- B. Turbulent
- C. Steady
- D. Irrotational
Explanation: A velocity potential exists when the flow is irrotational, meaning the curl of the velocity field is zero.
Correct answer: Irrotational- A. Rotameter
- B. Orificemeter
- C. Anemometer
- D. Venturimeter
Explanation: A rotameter is a variable-area meter: the float position changes the annular flow area until the pressure force and weight balance.
Correct answer: Rotameter- A. Fanning equation
- B. Blake-Plummer equation
- C. Hagen-Poiseuille equation
- D. Kozeny-Carman equation
Explanation: At very large packed-bed Reynolds numbers, inertial losses dominate viscous losses, so the pressure drop varies approximately with the…
Correct answer: Blake-Plummer equation- A. Length is shorter
- B. Throat diameter is more
- C. Sudden expansion of flow in the downstream occurs
- D. Distance between the throat and the inlet is more
Explanation: A flow nozzle has a comparatively abrupt discharge and therefore produces a sudden expansion downstream, causing greater eddy and…
Correct answer: Sudden expansion of flow in the downstream occurs- A. Globe valve
- B. Plug-cock
- C. Check valve
- D. Gate valve
Explanation: Gate valves provide a relatively unobstructed passage and are economical in large pipe sizes, so they are commonly selected above about 2…
Correct answer: Gate valve- A. 1
- B. 1.5
- C. 2
- D. 2.5
Explanation: Laminar flow between parallel plates has a parabolic velocity profile, with maximum velocity at the mid-plane.
Correct answer: 1.5- A. 90° and 80°
- B. 45° and 60°
- C. 40° and 140°
- D. 20° and 120°
Explanation: In a double-acting reciprocating pump, the air vessel supplies or receives flow during much of the cycle, but its flow becomes zero at the…
Correct answer: 40° and 140°4192. For the same terminal conditions and fitting size, the least friction loss is incurred in a/an ?
- A. T-joint
- B. 90°bend
- C. 45° elbow
- D. Union
Explanation: A union has a comparatively small change in flow direction and cross-sectional area, so its minor-loss coefficient is lower than those of…
Correct answer: Union- A. Bell and spigot joint
- B. Welding
- C. Soldering
- D. Flanges
Explanation: Glass pipes are commonly connected with bell-and-spigot joints, using a packing or sealing material to accommodate the rigid, brittle…
Correct answer: Bell and spigot joint- A. Q1/Q2
- B. (Q2 - Q1)/Q2
- C. (Q2 - Q1)/Q1
- D. Q2/Q1
Explanation: Slip is the loss of discharge relative to the theoretical discharge, so percentage slip is 100 times (Q2 − Q1)/Q2.
Correct answer: (Q2 - Q1)/Q2- A. Geometrical similarity only
- B. All geometrical, dynamic and kinematic similarity
- C. Both geometrical and dynamic similarity
- D. Dynamic similarity only
Explanation: Reliable agitator scale-up requires geometrical similarity along with dynamic and kinematic similarity so that the flow pattern and force…
Correct answer: All geometrical, dynamic and kinematic similarity- A. Is independent of the area of flow
- B. Is constant
- C. Decreases in the downstream direction
- D. Increases in the downstream direction
Explanation: For subsonic compressible flow in a pipeline, friction causes the fluid to accelerate downstream toward sonic conditions, so its velocity…
Correct answer: Increases in the downstream direction- A. Energy is constant along a stream line, but may vary across stream lines
- B. Energy is constant throughout the fluid
- C. Velocity is constant along a stream line
- D. None of these
Explanation: Bernoulli's equation expresses conservation of mechanical energy along a streamline for steady, ideal, inviscid flow.
Correct answer: Energy is constant along a stream line, but may vary across stream lines- A. I, II, III
- B. II, III, V
- C. I, II, V
- D. II, IV, V
Explanation: Newton's second law and continuity apply to fluid motion, while an impermeable boundary cannot be penetrated, giving the normal-velocity…
Correct answer: II, III, V- A. Compress air
- B. Lift compressed air
- C. Lift water from a well by using compressed air
- D. Lift air under negative pressure
Explanation: An air-lift pump injects compressed air into a liquid column, reducing its average density so the water rises through the delivery pipe.
Correct answer: Lift water from a well by using compressed air- A. Increase
- B. Data insufficient to predict
- C. Remain same
- D. Decrease
Explanation: At the same flow rate and pump head, power is proportional to the liquid's specific weight.
Correct answer: Decrease