chemical engineering MCQs – Page 322

Practise multiple-choice questions from chemical engineering for competitive examinations and subject revision. Review each marked answer and report any item that may be outdated or unclear.

chemical engineering Mcqs
6421. At what value of crank angle (roughly), no flow of water from or into the air vessel takes place in case of a double acting reciprocating pump ?
comments icon0

A. 45 and 60

B. 90 and 80

C. 40 and 140

D. 20 and 120

6422. The effect of solid boundary on the fluid flow is confined to the boundary layer, except for fluids ?
comments icon0

A. Having high viscosities

B. Moving at low velocities

C. Both A. & B.

D. Neither A. nor B.

6423. Weber number is the ratio of inertial force to _____________ force?
comments icon0

A. Elastic

B. Surface tension

C. Gravity

D. Viscous

6424. The velocity profile exhibited by laminar flow of Newtonian fluids is such that the velocity distribution w.r.t. radius of the circular pipe is a/an ______________ with the apex at the centre line of the pipe?
comments icon0

A. Semi-circle

B. Semi-ellipse

C. Hyperbola

D. Parabola
6425. Glass pipes can be joined by__________________?
comments icon0

A. Flanges

B. Welding

C. Bell and spigot joint

D. Soldering

6426. Multistage compressors are used in industry, because they____________________?
comments icon0

A. Reduce the cost of compressor

B. Resemble closely to isothermal compression

C. Reduce the size requirement

D. Are easy to control

6427. The discharge through a rectangular weir varies as ___________________?
comments icon0

A. H5/2

B. H2/5

C. H1/2

D. H3/2
6428. The excess of the sum of pressure & velocity heads over the vapor pressure of the liquid at the suction is called the___________________?
comments icon0

A. Static submergence

B. Priming

C. Net positive suction head (NPSH)

D. Cavitation sensitivity

6429. ____________ flow means the flow of incompressible fluid with no shear ?
comments icon0

A. Streamline

B. Creep

C. Boundary layer

D. Potential
6430. In turbulent flow, the__________________?
comments icon0

A. Momentum transfer is on molecular scale only

B. Fluid particles move in an orderly manner

C. Shear stresses are generally larger than in a similar laminar flow

D. Shear stress is caused more effectively by cohesion than momentum transfer

6431. The capacity of a centrifugal pump Can be increased by increasing the_________________?
comments icon0
A. All A., B. and C.

B. Impeller diameter or speed

C. Number of pumps and joining them in series

D. Number of pumps and joining them in parallel

6432. A centrifugal pump designed to pump water is employed to pump a more viscous oil. In the later case, the pump_________________?
comments icon0

A. Requires more power

B. Capacity is reduced

C. All A., B. and C.

D. Develops a lower head

6433. The most serious disadvantage of an orificemeter is that________________?
comments icon0

A. It is not very accurate

B. Most of the pressure drop is not recoverable

C. It is very costly

D. It is not suitable for measuring gas flow

6434. The ratio of inertial forces to elastic forces is called the __________ number?
comments icon0

A. Euler

B. Reynolds

C. Weber

D. Mach
6435. Mach number is defined as the ratio of the local flow velocity to the sonic velocity in the fluid. For what value of Mach number, the gases are considered incompressible ?
comments icon0
A. < 0.3

B. 1

C. 50

D. > 3

6436. For an incompressible fluid, the bulk modulus of elasticity is____________________?
comments icon0

A. 5 kg/m3

B. 0 N/m

C. 1 N

D. ? N/m2
6437. Which of the following exemplifies a three dimensional fluid flow ?
comments icon0

A. Viscous fluid flow between converging plates

B. Fluid flow between parallel plates

C. None of these

D. Fluid flow at the inlet to a nozzle
6438. With increase in the shear rate, the apparent viscosity of pseudo-plastic fluids__________________?
comments icon0

A. Increases

B. May increase or decrease; depends on the magnitude of shear rate

C. Decreases

D. Remain same

6439. Dimension of kinematic viscosity is_____________________?
comments icon0
A. L2T-1

B. L2T

C. MLT-1

D. L2T-2

6440. The buoyant force acting on a floating body is dependent on the _______________?
comments icon0
A. Weight of the liquid displaced

B. Surface tension of the liquid

C. Viscosity of the liquid

D. Depth of immersion of the body