Explore topic-wise MCQs in Chemical Engineering.

This section includes 1608 Mcqs, each offering curated multiple-choice questions to sharpen your Chemical Engineering knowledge and support exam preparation. Choose a topic below to get started.

1351.

With a constant diameter impeller of a centrifugal pump

A. its capacity varies directly as the square of speed.
B. head varies as the square of speed.
C. horsepower input varies as the square of speed.
D. head varies as the speed.
Answer» C. horsepower input varies as the square of speed.
1352.

Pressure difference between two points in vessels, pipelines or in two different pipelines can be measured by a differential manometer. The pressure difference measured as the mm of water coloumn in case of mercury-water, differential manometer is equal to (where, H = difference in height of mercury column in mm).

A. H
B. 12.6 H
C. 13.6 H
D. 14.6 H
Answer» C. 13.6 H
1353.

Steady flow occurs, when the

A. conditions change steadily with time.
B. conditions are the same at the adjacent points at any instant.
C. conditions do not change with time at any point.
D. rate of the velocity change is constant.
Answer» D. rate of the velocity change is constant.
1354.

Flow rate of high velocity flue gas discharged through a stack to the atmosphere can be most conveniently measured by a

A. pitot tube
B. manometer
C. rotameter
D. none of these
Answer» B. manometer
1355.

For a reciprocating pump, the indicator diagram is the graph between the

A. discharge and overall efficiency.
B. volume swept by piston for one complete revolution and the pressure in the cylinder.
C. angle swept by the crank pin at any instant and the discharge.
D. none of these.
Answer» C. angle swept by the crank pin at any instant and the discharge.
1356.

Where does the maximum stress occur in case of laminar flow of incompressible fluid in a closed conduit of diameter 'd'?

A. At the centre
B. At d/4 from the wall
C. At the wall
D. At d/8 from the wall
Answer» D. At d/8 from the wall
1357.

Cavitation occurs in a centrifugal pump when the suction pressure is

A. less than the vapour pressure of the liquid at that temperature.
B. greater than the vapour pressure of the liquid at that temperature.
C. equal to the vapour pressure.
D. equal to the developed head.
Answer» B. greater than the vapour pressure of the liquid at that temperature.
1358.

The unit of bulk modulus of elasticity for a liquid in S.I. unit is

A. N
B. N/m
C. N/m2
D. N/m3
Answer» D. N/m3
1359.

With increase in the schedule number of a pipe of a particular nominal size, the

A. wall thickness also increases.
B. I.D. of the pipe decreases.
C. O.D. of the pipe remains constant.
D. all (a), (b) and (c)
Answer» E.
1360.

Fluid flow in a/an __________ is an example of pressure flow.

A. partially filled pipeline
B. pipe
C. open channel
D. river.
Answer» C. open channel
1361.

For water, when the pressure increases, the viscosity

A. also increases
B. decreases
C. remains constant
D. first decreases, and then increases
Answer» E.
1362.

One dimensional flow implies

A. flow in a straight line.
B. steady uniform flow.
C. unsteady uniform flow.
D. a flow which does not account for changes in transverse direction.
Answer» E.
1363.

The boundary layer thickness at a given section along a flat plate __________ with increasing Reynold's number.

A. increases
B. decreases
C. remains same
D. may increase or decrease
Answer» C. remains same
1364.

For an incompressible fluid, the bulk modulus of elasticity is

A. 5 kg/m3
B. ‚àû N/m2
C. 1 N
D. 0 N/m
Answer» C. 1 N
1365.

Unsteady uniform flow is represented by flow through a/an

A. long pipe at constant rate.
B. long pipe at decreasing rate.
C. expanding tube at increasing rate.
D. expanding tube at constant rate.
Answer» C. expanding tube at increasing rate.
1366.

In case of turbulent flow of fluid through a circular pipe, the

A. mean flow velocity is about 0.5 times the maximum velocity.
B. velocity profile becomes flatter and flatter with increasing Reynolds number.
C. point of maximum instability exists at a distance of 2r/3 from the pipe wall (r = pipe radius).
D. skin friction drag, shear stresses, random orientation of fluid particles and slope of velocity profile at the wall are more.
Answer» E.
1367.

Dimension of surface tension is(where, F = force, L = length)

A. FL-1
B. F-1 . L
C. F.L-2
D. F-2 . L
Answer» B. F-1 . L
1368.

A fluid is pumped at the rate of 10 lb/sec to a height of 55 ft. The horse power required is __________ hp.

A. 1
B. 20363
C. 5.5
D. 20090
Answer» B. 20363
1369.

The momentum correction factor for the velocity distribution of laminar flow is

A. 1.3
B. 1.66
C. 2.5
D. none of these
Answer» E.
1370.

The schedule number of a pipe is an indication of its

A. size
B. roughness
C. material density
D. wall thickness
Answer» E.
1371.

The ratio of the depth of flow to the hydraulic radius for the most economical trapezoidal section, in open channel flow is

A. 0.5
B. 1
C. 1.5
D. 2
Answer» E.
1372.

All pipes of a particular nominal size have the same

A. inside diameter
B. outside diameter
C. thickness
D. none of these
Answer» C. thickness
1373.

Very small pressure difference (< 5 mm water coloumn) can be most conveniently measured by a/an __________ manometer.

A. U-tube water.
B. U-tube mercury.
C. inclined tube mercury.
D. inclined tube water.
Answer» E.
1374.

A centrifugal pump designed to pump water is employed to pump a more viscous oil. In the later case, the pump

A. develops a lower head.
B. capacity is reduced.
C. requires more power.
D. all (a), (b) and (c).
Answer» E.
1375.

Hydraulic __________ works on the principle of Pascal's law of transmission of fluid pressure.

A. press
B. turbine
C. pump
D. coupling
Answer» B. turbine
1376.

Acceleration head in a reciprocating pump

A. increases the work done during delivery stroke.
B. decreases the work done during suction stroke.
C. does not change the work requirement of the pump.
D. increases the work done during suction stroke.
Answer» D. increases the work done during suction stroke.
1377.

A mixed flow centrifugal pump

A. employs such an impeller, through which the flow is a combination of radial & axial flow.
B. mixes the two fluids before pumping them.
C. pumps the two fluids separately and then mixes them.
D. employs impellers in both the radial & axial directions.
Answer» B. mixes the two fluids before pumping them.
1378.

The dimension of surface tension is

A. ML-2
B. MT-2
C. MLT-2
D. ML-2T
Answer» C. MLT-2
1379.

Working principle of manometer comprises of balancing a coloumn of liquid against the pressure to be measured. Inclined tube manometer is especially used for the measurement of __________ pressure.

A. small differential
B. atmospheric
C. absolute
D. gage
Answer» B. atmospheric
1380.

The ratio of inertial forces to gravity forces is called the __________ number.

A. Mach
B. Froude
C. Euler
D. Weber
Answer» C. Euler
1381.

The __________ pressure is measured by a static tube.

A. dynamic
B. static
C. total
D. none of these
Answer» C. total
1382.

Boundary layer thickness in laminar flow over a flat plate increases as(where, d = distance from the leading edge.)

A. d
B. d1/3
C. d2
D. d2/3
Answer» B. d1/3
1383.

Minimum fluidisation velocity for a specific system depends upon the

A. particle size.
B. fluid viscosity.
C. density of both the particle & the fluid.
D. all (a), (b) and (c).
Answer» E.
1384.

Maximum theoretical suction lift for water at 15°C by a centrifugal pump is 34 ft. The same for water at 90°C will be __________ ft.$

A. 40
B. 34
C. 8
D. 37
Answer» D. 37
1385.

Weber number is the ratio of inertial force to __________ force.

A. surface tension
B. gravity
C. viscous
D. elastic
Answer» B. gravity
1386.

Out of the following flow measuring devices, which one incurs the maximum installation cost as well as pressure loss ?

A. Flow nozzle
B. Venturimeter
C. Rotameter
D. Orificemeter
Answer» C. Rotameter
1387.

The ratio of pressure forces to inertial forces is called the __________ number.

A. Froude
B. Euler
C. Reynold
D. Mach
Answer» C. Reynold
1388.

A mono pump is a __________ pump.

A. centrifugal
B. piston
C. positive acting rotary
D. a group of vacuum
Answer» D. a group of vacuum
1389.

Navier-Stokes equation is useful in the analysis of __________ fluid flow problems.

A. non-viscous
B. viscous
C. turbulent
D. rotational
Answer» C. turbulent
1390.

In case of venturimeters, friction losses are about __________ percent of maximum velocity head.

A. 2
B. 8
C. 12
D. 20
Answer» B. 8
1391.

Open channel liquid flow is most conveniently measured by a

A. hot wire anemometer
B. notch
C. rotameter
D. segmental orifice
Answer» C. rotameter
1392.

Consider a centrifugal pump having a specific impeller diameter, fixed impeller speed pumping a liquid of constant density at a particular discharge capacity. With decrease in the capacity of the pump, the __________ decreases.

A. NPSH required.
B. BHP required by the pump.
C. head of the liquid pumped.
D. all (a), (b) and (c).
Answer» E.
1393.

The ratio of average fluid velocity to the maximum velocity in case of laminar flow of a Newtonion fluid in a circular pipe is

A. 0.5
B. 1
C. 2
D. 0.66
Answer» B. 1
1394.

Nominal Pipe Size (NPS) of a pipe less than 12 inches in diameter indicates its

A. inner diameter
B. outer diameter
C. thickness
D. neither inner nor outer diameter
Answer» E.
1395.

The net positive suction head (NPSH) of a centrifugal pump is defined as the sum of the velocity head and the pressure head at the

A. discharge.
B. suction.
C. suction minus vapor pressure of the liquid at suction temperature.
D. discharge minus vapor pressure of the liquid at the discharge temperature.
Answer» D. discharge minus vapor pressure of the liquid at the discharge temperature.
1396.

Which of the following pipe bends will incur the largest head loss ?

A. U-bend
B. 30° bend
C. 45° bend
D. 90° bend
Answer» B. 30¬∞ bend
1397.

Enamels and paints are generally __________ fluid.

A. reheopectic
B. pseudo-plastic
C. thixotropic
D. dilatant
Answer» C. thixotropic
1398.

Which of the following can be used for the direct measurement of volumetric flow rate of slurry ?

A. Venturimeter
B. Orificemeter
C. Rotameter
D. Pitot tube
Answer» D. Pitot tube
1399.

Pick out the correct statement pertaining to the flow through a converging-diverging tube.

A. The value of Mach number is always unity at the throat.
B. No shock wave develops in the tube when the Mach number at exit is greater than unity.
C. Throughout the converging portion of the tube, the density increases in the downstream direction.
D. none of these.
Answer» C. Throughout the converging portion of the tube, the density increases in the downstream direction.
1400.

Velocity at a certain point in case of streamline flow is

A. constant
B. independent of time
C. both (a) & (b)
D. neither (a) nor (b)
Answer» D. neither (a) nor (b)