Self-priming centrifugal pump can be used for

pumping liquid fertilisers (e.g. liquid NH3).

In a fluidised bed reactor

temperature gradients are very high.

temperature is more or less uniform.

segregation of the solids occurs.

The head loss in turbulent flow in a pipe varies

inversely as the square of diameter

The continuity equation

relates mass flow rate along a stream tube.

stipulates that Newton's second law of motion must be satisfied at every point in the fluid.

In case of hydraulically smooth pipe, the resistance to flow depends only on the Reynolds number, whereas for a hydraulically rough pipe, the resistance to flow is governed by the relative roughness. Two pipes are said to have the same hydraulic roughness, when they have equal values of

friction co-efficient for flows at equal Reynold number.

Fluidised beds are formed, when the

pressure forces equal gravity forces.

gravity force is less than the fluid friction.

pressure forces equal gravity forces.

sum of the fluid friction and pressure forces is equal and opposite to gravity forces.

Differential manometer measures the

pressure difference between two points.

Poise is converted into stoke by

multiplying with specific gravity.

multiplying with density (gm/c.c).

multiplying with specific gravity.

Froude number is not a factor

for Reynolds number greater than 300.

when there is no vortex formation.

For motion of spherical particles in a stationary fluid, the drag co-efficient in hindered settling compared to that in free settling is

more or less, depending on the type of particle

In case of end to end connection of two or more pipes in series, the __________ each pipe.

same rate of flow passes through

rate of flow in each pipe is proportional to the length of

total flow rate is the sum of flow rate in

Pressure drag does not depend upon the

roughness of surface of the body.

length of the body in flow direction.

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

velocity profile varies hyperbolically and the shear stress remains constant over the cross-section.

shear stress over the cross-section is proportional to the distance from the surface of the pipe.

surface of velocity distribution is a paraboloid of revolution, whose volume equals half the volume of circumscribing cylinder.

velocity profile varies hyperbolically and the shear stress remains constant over the cross-section.

average flow occurs at a radial distance of 0.5 r from the centre of the pipe (r = pipe radius).

a constant velocity with no acceleration.

attained after moving one-half of total distance.

An isentropic process is the one, in which

pvr = constant, and process is reversible

The distribution of shear stress in a stream of fluid in a circular tube is

parabolic with radius for both laminar & turbulent flow.

linear with radius for turbulent flow only.

linear with radius for laminar flow only.

linear with radius for both laminar & turbulent flow.

parabolic with radius for both laminar & turbulent flow.

In fluid flow, the boundary layer separation can not occur

in case of boundaries experiencing form drag.

at points of abrupt changes in the flow directions.

Air vessel provided in a reciprocating pump is for

decreasing the acceleration head.

increasing the acceleration head.

making the friction in pipe uniform.

decreasing the acceleration head.

1608 + Mcqs in Fluid Mechanics in Chemical Engineering Page 30 McqOptions

1451.	Self-priming centrifugal pump can be used for
A.	booster service.
B.	pumping liquid fertilisers (e.g. liquid NH3).
C.	pumping industrial wastes.
D.	all (a), (b) and (c).
Answer» E.

Discussion

1452.	The head loss in turbulent flow in pipe is proportional to(where, V = velocity of fluid through the pipe)
A.	V2
B.	1/V2
C.	1/V
D.	V
Answer» B. 1/V2

Discussion

1453.	Brownian movement is prominent in the particle size range of __________ microns in case of settling of a particle in a fluid.
A.	2 to 3
B.	0.01 to 0.10
C.	200 to 300
D.	100 to 1000
Answer» B. 0.01 to 0.10

Discussion

1454.	In a fluidised bed reactor
A.	temperature gradients are very high.
B.	temperature is more or less uniform.
C.	hot spots are formed.
D.	segregation of the solids occurs.
Answer» C. hot spots are formed.

Discussion

1455.	The head loss in turbulent flow in a pipe varies
A.	as velocity
B.	as (velocity)2
C.	inversely as the square of diameter
D.	inversely as the velocity
Answer» C. inversely as the square of diameter

Discussion

1456.	A rotameter works on the principle of __________ pressure drop.
A.	constant
B.	variable
C.	both (a) & (b)
D.	neither (a) nor (b)
Answer» B. variable

Discussion

1457.	Steady fluid flow occurs, when the derivative of flow variables satisfy the following condition.
A.
B.
C.
D.
Answer» C.

Discussion

1458.	What causes convective acceleration in fluid flow ?
A.	Steep slope in flow
B.	Unsteady nature of flow
C.	Non-uniformity of flow
D.	Turbulence in flow
Answer» D. Turbulence in flow

Discussion

1459.	The pressure drop per unit length of pipe incurred by a fluid 'X' flowing through pipe is Œîp. If another fluid 'Y' having both the specific gravity & density just double of that of fluid 'X', flows through the same pipe at the same flow rate/average velocity, then the pressure drop in this case will be
A.	Œîp
B.	2Œîp
C.	Œîp2
D.	Œîp/2
Answer» C. Œîp2

Discussion

1460.	What is the normal range of exit cone angle of a venturimeter ?
A.	2 to 5
B.	7 to 15
C.	15 to 25
D.	>25
Answer» C. 15 to 25

Discussion

1461.	The equation relating friction factor to Reynold number, f-0.5 = 4 loge (NRe/f)-0.4, is called the __________ equation.
A.	Nikuradse
B.	Von-Karman
C.	Blausius
D.	Colebrook
Answer» B. Von-Karman

Discussion

1462.	In a dry packed bed, the pressure drop will be changed by increasing the flow rate as
A.	V1.8
B.	V-0.8
C.	V
D.	V-1
Answer» B. V-0.8

Discussion

1463.	The continuity equation
A.	relates mass flow rate along a stream tube.
B.	relates work and energy.
C.	stipulates that Newton's second law of motion must be satisfied at every point in the fluid.
D.	none of these.
Answer» B. relates work and energy.

Discussion

1464.	For flow through a venturi at a particular discharge, the correct relationships among velocities at point X, Y and Z would be
A.	V1 < V2 < V3
B.	V2 > V1 and V2 > V3
C.	V1 > V2 > V3
D.	none of these.
Answer» C. V1 > V2 > V3

Discussion

1465.	The equivalent diameter for fluid flow through square cross section channel of side 'x', for pressure drop calculation purpose is given by
A.	4x
B.	2x
C.	x
D.	x
Answer» D. x

Discussion

1466.	The fluid in which the shearing stress within it is proportional to the velocity gradient across the sheared section, is called a __________ fluid.
A.	Bingham
B.	Newtonion
C.	perfect
D.	none of these
Answer» C. perfect

Discussion

1467.	In case of hydraulically smooth pipe, the resistance to flow depends only on the Reynolds number, whereas for a hydraulically rough pipe, the resistance to flow is governed by the relative roughness. Two pipes are said to have the same hydraulic roughness, when they have equal values of
A.	relative roughness.
B.	absolute roughness.
C.	friction co-efficient for flows at equal Reynold number.
D.	all (a), (b) & (c).
Answer» D. all (a), (b) & (c).

Discussion

1468.	A bed of spherical particles (specific gravity 2.5) of uniform size 1500 Œºm is 0.5 m in diameter and 0.5 m high. In packed bed state, the porosity may be taken as 0.4. Ergun's equation for the above fluid-particle system (in SI units) is given below : Œî P/L = 375 x 103 VOM + 10.94 x 106 V2OM (SI units) If water is to be used as the fluidising medium, in actual operation, the above bed has a height = 1 m. What is the porosity of the fluidised bed ?
A.	0.2
B.	0.5
C.	0.7
D.	0.8
Answer» D. 0.8

Discussion

1469.	Fluidised beds are formed, when the
A.	fluid friction is zero
B.	gravity force is less than the fluid friction.
C.	pressure forces equal gravity forces.
D.	sum of the fluid friction and pressure forces is equal and opposite to gravity forces.
Answer» C. pressure forces equal gravity forces.

Discussion

1470.	A hydraulic ram acts as a/an __________ pump.
A.	centrifugal
B.	reciprocating
C.	impulse
D.	parallel cylinder
Answer» D. parallel cylinder

Discussion

1471.	Differential manometer measures the
A.	atmospheric pressure.
B.	sub-atmospheric pressure.
C.	pressure difference between two points.
D.	none of these.
Answer» D. none of these.

Discussion

1472.	Poise is converted into stoke by
A.	multiplying with density (gm/c.c).
B.	dividing by density (gm/c.c).
C.	multiplying with specific gravity.
D.	dividing by specific gravity.
Answer» C. multiplying with specific gravity.

Discussion

1473.	The fluid property which matters for fall-ing rain drops to acquire spherical shape is its
A.	pressure
B.	height of descend
C.	viscosity
D.	surface tension
Answer» E.

Discussion

1474.	Check valve is used for __________ flow.
A.	very precise control of
B.	unidirectional
C.	multidirectional
D.	none of these
Answer» C. multidirectional

Discussion

1475.	If the discharge of a centrifugal pump is throttled, then its suction lift
A.	increases
B.	decreases
C.	remains unchanged
D.	data insufficient to predict
Answer» B. decreases

Discussion

1476.	Froude number is not a factor
A.	for Reynolds number greater than 300.
B.	when there is no vortex formation.
C.	for unbaffled tank.
D.	none of these.
Answer» C. for unbaffled tank.

Discussion

1477.	For motion of spherical particles in a stationary fluid, the drag co-efficient in hindered settling compared to that in free settling is
A.	more
B.	less
C.	equal
D.	more or less, depending on the type of particle
Answer» B. less

Discussion

1478.	In case of end to end connection of two or more pipes in series, the __________ each pipe.
A.	same rate of flow passes through
B.	head loss is same through
C.	rate of flow in each pipe is proportional to the length of
D.	total flow rate is the sum of flow rate in
Answer» B. head loss is same through

Discussion

1479.	Diaphragm pumps are used to transport
A.	solids
B.	liquids
C.	fluids
D.	slurries
Answer» E.

Discussion

1480.	The rate of shear versus the shear stress curves are time dependent for __________ fluid.
A.	thixotropic
B.	rheopectic
C.	both (a) & (b)
D.	neither (a) nor (b)
Answer» D. neither (a) nor (b)

Discussion

1481.	Velocity of liquid hydrocarbon fuels in a pipeline can not be measured by magnetic flowmeters, because their __________ is very low/small.
A.	thermal conductivity
B.	electrical conductivity
C.	specific gravity
D.	electrical resistivity
Answer» C. specific gravity

Discussion

1482.	Pressure drag does not depend upon the
A.	roughness of surface of the body.
B.	pressure of main flow only.
C.	length of the body in flow direction.
D.	all (a), (b) and (c)
Answer» E.

Discussion

1483.	A stream tube is that, which has __________ cross-section entirely bounded by stream lines.
A.	a circular
B.	any convenient
C.	a small
D.	a large
Answer» C. a small

Discussion

1484.	Potential function is applicable only for __________ flow.
A.	irrotational
B.	turbulent
C.	steady
D.	none of these
Answer» B. turbulent

Discussion

1485.	In case of laminar flow of fluid through a circular pipe, the
A.	shear stress over the cross-section is proportional to the distance from the surface of the pipe.
B.	surface of velocity distribution is a paraboloid of revolution, whose volume equals half the volume of circumscribing cylinder.
C.	velocity profile varies hyperbolically and the shear stress remains constant over the cross-section.
D.	average flow occurs at a radial distance of 0.5 r from the centre of the pipe (r = pipe radius).
Answer» C. velocity profile varies hyperbolically and the shear stress remains constant over the cross-section.

Discussion

1486.	In case of isentropic flow, the speed of sound in an ideal gas is proportional to (where, T = absolute temperature )
A.	1/T
B.	1/T
C.	T
D.	T
Answer» D. T

Discussion

1487.	Horsepower requirement for given pump capacity depends upon the
A.	specific gravity of the liquid
B.	suction lift
C.	discharge head
D.	all (a), (b) and (c)
Answer» E.

Discussion

1488.	The curve of metacentre for a floating body __________ the curve of buoyancy.
A.	is always below
B.	is the evolute of
C.	intersects at right angle
D.	is tangential to
Answer» C. intersects at right angle

Discussion

1489.	__________ isused for measuring the static pressure exerted on the wall by a fluid flowing parallel to the wall in a pipeline.
A.	Venturimeter
B.	Pressure gauge
C.	Pitot tube
D.	Orificemeter
Answer» D. Orificemeter

Discussion

1490.	Rubber latex is an example of a __________ .fluid.
A.	pseudoplastic
B.	bingham plastic
C.	dilatent
D.	Newtonion
Answer» B. bingham plastic

Discussion

1491.	Reynolds number for flow of water at room temperature through 2 cm dia pipe at an average velocity of 5 cm/sec is around
A.	2000
B.	10
C.	100
D.	1000
Answer» E.

Discussion

1492.	Terminal velocity is
A.	a constant velocity with no acceleration.
B.	a fluctuating velocity.
C.	attained after moving one-half of total distance.
D.	none of these.
Answer» B. a fluctuating velocity.

Discussion

1493.	An isentropic process is the one, in which
A.	pv = constant
B.	pvr = constant
C.	pvr = constant, and process is reversible
D.	none of these
Answer» D. none of these

Discussion

1494.	The distribution of shear stress in a stream of fluid in a circular tube is
A.	linear with radius for turbulent flow only.
B.	linear with radius for laminar flow only.
C.	linear with radius for both laminar & turbulent flow.
D.	parabolic with radius for both laminar & turbulent flow.
Answer» D. parabolic with radius for both laminar & turbulent flow.

Discussion

1495.	In fluid flow, the boundary layer separation can not occur
A.	in case of boundaries experiencing form drag.
B.	at points of abrupt changes in the flow directions.
C.	in laminar flow.
D.	none of these.
Answer» E.

Discussion

1496.	Air vessel provided in a reciprocating pump is for
A.	increasing the acceleration head.
B.	making the friction in pipe uniform.
C.	decreasing the acceleration head.
D.	none of these.
Answer» C. decreasing the acceleration head.

Discussion

1497.	Maintenance cost of a __________ pump for a particular duty is the least.
A.	centrifugal
B.	reciprocating
C.	volute
D.	gear
Answer» B. reciprocating

Discussion

1498.	The ratio of wall drag to total drag in the Stoke's law range is
A.	0.5
B.	1
C.	43525
D.	43526
Answer» E.

Discussion

1499.	If two capillary tubes of dia 0.5 mm and 1 mm are dipped in a pot containing mercury, then the rise of mercury is
A.	same in both the tubes.
B.	greater in 1 mm dia tube.
C.	greater in 0.5 mm dia tube.
D.	zero in both the tubes.
Answer» D. zero in both the tubes.

Discussion

1500.	Stoke's law is valid, when the particle Reynolds number is
A.	< 1
B.	> 1
C.	< 5
D.	none of these
Answer» B. > 1

Discussion

Explore topic-wise MCQs in Chemical Engineering.

Self-priming centrifugal pump can be used for

The head loss in turbulent flow in pipe is proportional to(where, V = velocity of fluid through the pipe)

Brownian movement is prominent in the particle size range of __________ microns in case of settling of a particle in a fluid.

In a fluidised bed reactor

The head loss in turbulent flow in a pipe varies

A rotameter works on the principle of __________ pressure drop.

Steady fluid flow occurs, when the derivative of flow variables satisfy the following condition.

What causes convective acceleration in fluid flow ?

What is the normal range of exit cone angle of a venturimeter ?

The equation relating friction factor to Reynold number, f-0.5 = 4 loge (NRe/f)-0.4, is called the __________ equation.

In a dry packed bed, the pressure drop will be changed by increasing the flow rate as

The continuity equation

For flow through a venturi at a particular discharge, the correct relationships among velocities at point X, Y and Z would be

The equivalent diameter for fluid flow through square cross section channel of side 'x', for pressure drop calculation purpose is given by

The fluid in which the shearing stress within it is proportional to the velocity gradient across the sheared section, is called a __________ fluid.

In case of hydraulically smooth pipe, the resistance to flow depends only on the Reynolds number, whereas for a hydraulically rough pipe, the resistance to flow is governed by the relative roughness. Two pipes are said to have the same hydraulic roughness, when they have equal values of

Fluidised beds are formed, when the

A hydraulic ram acts as a/an __________ pump.

Differential manometer measures the

Poise is converted into stoke by

The fluid property which matters for fall-ing rain drops to acquire spherical shape is its

Check valve is used for __________ flow.

If the discharge of a centrifugal pump is throttled, then its suction lift

Froude number is not a factor

For motion of spherical particles in a stationary fluid, the drag co-efficient in hindered settling compared to that in free settling is

In case of end to end connection of two or more pipes in series, the __________ each pipe.

Diaphragm pumps are used to transport

The rate of shear versus the shear stress curves are time dependent for __________ fluid.

Velocity of liquid hydrocarbon fuels in a pipeline can not be measured by magnetic flowmeters, because their __________ is very low/small.

Pressure drag does not depend upon the

A stream tube is that, which has __________ cross-section entirely bounded by stream lines.

Potential function is applicable only for __________ flow.

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

In case of isentropic flow, the speed of sound in an ideal gas is proportional to (where, T = absolute temperature )

Horsepower requirement for given pump capacity depends upon the

The curve of metacentre for a floating body __________ the curve of buoyancy.

__________ isused for measuring the static pressure exerted on the wall by a fluid flowing parallel to the wall in a pipeline.

Rubber latex is an example of a __________ .fluid.

Reynolds number for flow of water at room temperature through 2 cm dia pipe at an average velocity of 5 cm/sec is around

Terminal velocity is

An isentropic process is the one, in which

The distribution of shear stress in a stream of fluid in a circular tube is

In fluid flow, the boundary layer separation can not occur

Air vessel provided in a reciprocating pump is for

Maintenance cost of a __________ pump for a particular duty is the least.

The ratio of wall drag to total drag in the Stoke's law range is

If two capillary tubes of dia 0.5 mm and 1 mm are dipped in a pot containing mercury, then the rise of mercury is

Stoke's law is valid, when the particle Reynolds number is