4791 + Mcqs in Mechanical Engineering McqOptions

1.	The water tube boilers produce steam at a __________ pressure than that of fire tube boilers.
A.	lower
B.	higher
Answer» C.

Discussion

2.	Steam engines are called external combustion engines.
A.	Yes
B.	No
Answer» B. No

Discussion

3.	A good steam boiler is one which produces maximum quantity of steam with the given fuel
A.	Agree
B.	Disagree
Answer» B. Disagree

Discussion

4.	Cut-off ratio is the ratio of
A.	swept volume to the volume at cut-off
B.	volume at cut-off to the clearance volume
C.	volume at cut-off to the swept volume
D.	clearance volume to the volume at cut-off
Answer» D. clearance volume to the volume at cut-off

Discussion

5.	For maximum discharge through a chimney, the temperature of flue gases inside the chimney should the slightly more than the atmospheric temperature.
A.	Correct
B.	Incorrect
Answer» B. Incorrect

Discussion

6.	The internal flue tubes of a Lancashire boiler are reduced in diameter at the back to provide access to the lower part of the boiler.
A.	True
B.	False
Answer» B. False

Discussion

7.	A device in which some portion of waste heat of flue gases is recovered to heat the air before it passes to the furnace for combustion purpose, is knwon as
A.	superheater
B.	air preheater
C.	economiser
D.	injector
Answer» C. economiser

Discussion

8.	In a fire tube boiler, the water is contained inside the tubes which are surrounded by flames and hot gases from outside.
A.	True
B.	False
Answer» C.

Discussion

9.	A Tandem type compound engine requires a larger flywheel.
A.	True
B.	False
Answer» B. False

Discussion

10.	An economiser is installed in a boiler primarily to
A.	superheat the steam
B.	reduce fuel consumption
C.	increase steam pressure
D.	all of these
Answer» C. increase steam pressure

Discussion

11.	The fire tubes in a Cochran boiler usually have __________ diameter.
A.	6.25 mm
B.	62.5 mm
C.	72.5 mm
D.	92.5 mm
Answer» C. 72.5 mm

Discussion

12.	A compound steam engine in which piston rods of high pressure and low pressure cylinders ' are attached to two different cranks set at 180 to each other, is called
A.	receiver type compound engine
B.	Tandem type compound engine
C.	Woolf type compound engine
D.	both (a) and (b)
Answer» D. both (a) and (b)

Discussion

13.	The heat balance sheet for the boiler shows the
A.	complete account of heat supplied by 1 kg of dry fuel and the heat consumed
B.	moisture present in the fuel
C.	steam formed by combustion of hygrogen per kg of fuel
D.	all of the above
Answer» B. moisture present in the fuel

Discussion

14.	The performance of a boiler is measured by the
A.	amount of water evaporated per hour
B.	steam produced in kg/h
C.	steam produced in kg/kg of fuel burnt
D.	all of these
Answer» E.

Discussion

15.	The evaporative capacity of a boiler is defined as the evaporation of 15.653 kg of water per hour from and at 100 C.
A.	Yes
B.	No
Answer» C.

Discussion

16.	The maximum heat loss is a boiler occurs due to
A.	moisture in fuel
B.	dry flue gases
C.	steam formation
D.	unburnt carbon
Answer» C. steam formation

Discussion

17.	The function of a governor is to keep the engine speed uniform at all load conditions.
A.	Correct
B.	Incorrect
Answer» B. Incorrect

Discussion

18.	The efficiency of the plant __________ with the mechanical draught.
A.	increases
B.	decreases
C.	remains constant
Answer» B. decreases

Discussion

19.	Bulk modulus of a fluid is the ratio of
A.	shear stress to shear strain
B.	increase in volume to the viscosity of fluid
C.	increase in pressure to the volumetric strain
D.	critical velocity to the viscosity of fluid
Answer» D. critical velocity to the viscosity of fluid

Discussion

20.	The pressure at a point 4 m below the free surface of water is
A.	19.24 kPa
B.	29.24 kPa
C.	39.24 kPa
D.	49.24 kPa
Answer» D. 49.24 kPa

Discussion

21.	The mercury does not wet the glass. This is due to the property of the liquid known as
A.	cohesion
B.	adhesion
C.	viscosity
D.	surface tension
Answer» E.

Discussion

22.	The coefficient of discharge in case of internal mouthpiece is __________ that of external mouthpiece.
A.	less than
B.	more than
Answer» B. more than

Discussion

23.	When the venturimeter is inclined, then for a given flow it will show __________ reading.
A.	same
B.	more
C.	less
Answer» B. more

Discussion

24.	The discharge through a channel of rectangular section will be maximum, if
A.	its depth is twice the breadth
B.	its breadth is twice the depth
C.	its depth is thrice the breadth
D.	its breadth is thrice the depth
Answer» C. its depth is thrice the breadth

Discussion

25.	The specific weight is also known as weight density.
A.	Correct
B.	Incorrect
Answer» B. Incorrect

Discussion

26.	In a lockgate, the reaction between two gates is (where P = Resultant pressure on the lock gate, and = Inclination of the gate with the normal to the side of the lock)
A.	<img src="/_files/images/mechanical-engineering/hydraulics-and-fluid-mechanics/153-71-1.png">
B.	<img src="/_files/images/mechanical-engineering/hydraulics-and-fluid-mechanics/153-71-2.png">
C.	P / 2sin
D.	<!-- img src="/_files/images/mechanical-engineering/hydraulics-and-fluid-mechanics/153-71-3.png" //-->
E.	<img src="/_files/images/mechanical-engineering/hydraulics-and-fluid-mechanics/153-71-4.png">
Answer» D. <!-- img src="/_files/images/mechanical-engineering/hydraulics-and-fluid-mechanics/153-71-3.png" //-->

Discussion

27.	The velocity of the liquid flowing through the divergent portion of a venturimeter
A.	remains constant
B.	increases
C.	decreases
D.	depends upon mass of liquid
Answer» D. depends upon mass of liquid

Discussion

28.	In a broad-crested weir, the discharge is maximum if the head of water on the downstream side of weir is __________ the head of water on the upstream side of weir.
A.	equal to
B.	one-third
C.	two-third
D.	three-fourth
Answer» D. three-fourth

Discussion

29.	Bernoulli's equation is applied to
A.	venturimeter
B.	orifice meter
C.	pitot tube
D.	all of these
Answer» E.

Discussion

30.	A fluid having no viscosity is known as
A.	real fluid
B.	ideal fluid
C.	newtonian fluid
D.	non-newtonian fluid
Answer» C. newtonian fluid

Discussion

31.	In the manufacturing of lead shots, the property of surface tension is utilised.
A.	Agree
B.	Disagree
Answer» B. Disagree

Discussion

32.	The total pressure on the top of a closed cylindrical vessel of radius (r) completely filled up with liquid of specific weight (w) and rotating at ( ) rad/s about its vertical axis, is
A.	<img src="/_files/images/mechanical-engineering/hydraulics-and-fluid-mechanics/174-295-1.png">
B.	<img src="/_files/images/mechanical-engineering/hydraulics-and-fluid-mechanics/174-295-2.png">
C.	<img src="/_files/images/mechanical-engineering/hydraulics-and-fluid-mechanics/174-295-3.png">
D.	<img src="/_files/images/mechanical-engineering/hydraulics-and-fluid-mechanics/174-295-4.png">
Answer» D. <img src="/_files/images/mechanical-engineering/hydraulics-and-fluid-mechanics/174-295-4.png">

Discussion

33.	A flow is called super-sonic if the
A.	velocity of flow is very high
B.	discharge is difficult to measure
C.	Mach number is between 1and 6
D.	none of these
Answer» D. none of these

Discussion

34.	An opening in the side of a tank or vessel such that the liquid surface with the tank is below the top edge of the opening, is called
A.	weir
B.	notch
C.	orifice
D.	none of these
Answer» C. orifice

Discussion

35.	According to Newton's law of viscosity, the shear stress on a layer of a fluid is __________ to the rate of shear strain.
A.	equal to
B.	directly proportional
C.	inversely proportional
Answer» C. inversely proportional

Discussion

36.	Venturimeter is used to
A.	measure the velocity of a flowing liquid
B.	measure the pressure of a flowing liquid
C.	measure the discharge of liquid flowing in a pipe
D.	measure the pressure difference of liquid flowing between two points in a pipe line
Answer» D. measure the pressure difference of liquid flowing between two points in a pipe line

Discussion

37.	A hemispherical tank of radius (R) containing liquid upto height (H1) has an orifice of cross-sectional area (a) at its bottom. The time required to lower the level of liquid from (H1) to (H2) will be
A.	<img src="/_files/images/mechanical-engineering/hydraulics-and-fluid-mechanics/162-166-1.png">
B.	<img src="/_files/images/mechanical-engineering/hydraulics-and-fluid-mechanics/162-166-2.png">
C.	<img src="/_files/images/mechanical-engineering/hydraulics-and-fluid-mechanics/162-166-3.png">
D.	none of the above
Answer» D. none of the above

Discussion

38.	The force present in a moving liquid is
A.	inertia force
B.	viscous force
C.	gravity force
D.	all of these
Answer» E.

Discussion

39.	The force per unit length is the unit of
A.	surface tension
B.	compressibility
C.	capillarity
D.	viscosity
Answer» B. compressibility

Discussion

40.	Kinematic viscosity is the product of dynamic viscosity and the density of the liquid.
A.	Yes
B.	No
Answer» C.

Discussion

41.	A notch is, usually, made of a metallic plate.
A.	Correct
B.	Incorrect
Answer» B. Incorrect

Discussion

42.	In an internal mouthpiece, if the jet after contraction expands and fills up the whole mouthpiece, then the mouthpiece is said to be running free.
A.	True
B.	False
Answer» C.

Discussion

43.	A channel is said to be of most economical cross-section, if
A.	it gives maximum discharge for a given cross-sectional area and bed slope
B.	it has minimum wetted perimeter
C.	it involves lesser excavation for the designed amount of discharge
D.	all of the above
Answer» E.

Discussion

44.	A pipe of length more than double the diameter of orifice fitted externally or internally to the orifice is called a
A.	notch
B.	weir
C.	mouthpiece
D.	nozzle
Answer» D. nozzle

Discussion

45.	The pressure at a stagnation point is always low.
A.	Agree
B.	Disagree
Answer» C.

Discussion

46.	When an internal mouthpiece is running full, the discharge through the mouthpiece is twice the discharge when it is running free.
A.	Correct
B.	Incorrect
Answer» C.

Discussion

47.	In two dimensional flow, the flow does not take place in a curve.
A.	True
B.	False
Answer» C.

Discussion

48.	The discharge through a channel of circular section will be maximum when the depth of water is __________ the diameter of the circular channel.
A.	0.34 times
B.	0.67 times
C.	0.81 times
D.	0.95 times
Answer» E.

Discussion

49.	When the Mach number is more than 6, the flow is called
A.	sub-sonic flow
B.	sonic flow
C.	super-sonic flow
D.	hyper-sonic flow
Answer» E.

Discussion

50.	Poise is the unit of viscosity in C.G.S. system of units.
A.	Agree
B.	Disagree
Answer» B. Disagree

Discussion

Explore topic-wise MCQs in Testing Subject.

The water tube boilers produce steam at a __________ pressure than that of fire tube boilers.

Steam engines are called external combustion engines.

A good steam boiler is one which produces maximum quantity of steam with the given fuel

Cut-off ratio is the ratio of

For maximum discharge through a chimney, the temperature of flue gases inside the chimney should the slightly more than the atmospheric temperature.

The internal flue tubes of a Lancashire boiler are reduced in diameter at the back to provide access to the lower part of the boiler.

A device in which some portion of waste heat of flue gases is recovered to heat the air before it passes to the furnace for combustion purpose, is knwon as

In a fire tube boiler, the water is contained inside the tubes which are surrounded by flames and hot gases from outside.

A Tandem type compound engine requires a larger flywheel.

An economiser is installed in a boiler primarily to

The fire tubes in a Cochran boiler usually have __________ diameter.

A compound steam engine in which piston rods of high pressure and low pressure cylinders ' are attached to two different cranks set at 180 to each other, is called

The heat balance sheet for the boiler shows the

The performance of a boiler is measured by the

The evaporative capacity of a boiler is defined as the evaporation of 15.653 kg of water per hour from and at 100 C.

The maximum heat loss is a boiler occurs due to

The function of a governor is to keep the engine speed uniform at all load conditions.

The efficiency of the plant __________ with the mechanical draught.

Bulk modulus of a fluid is the ratio of

The pressure at a point 4 m below the free surface of water is

The mercury does not wet the glass. This is due to the property of the liquid known as

The coefficient of discharge in case of internal mouthpiece is __________ that of external mouthpiece.

When the venturimeter is inclined, then for a given flow it will show __________ reading.

The discharge through a channel of rectangular section will be maximum, if

The specific weight is also known as weight density.

In a lockgate, the reaction between two gates is (where P = Resultant pressure on the lock gate, and = Inclination of the gate with the normal to the side of the lock)

The velocity of the liquid flowing through the divergent portion of a venturimeter

In a broad-crested weir, the discharge is maximum if the head of water on the downstream side of weir is __________ the head of water on the upstream side of weir.

Bernoulli's equation is applied to

A fluid having no viscosity is known as

In the manufacturing of lead shots, the property of surface tension is utilised.

The total pressure on the top of a closed cylindrical vessel of radius (r) completely filled up with liquid of specific weight (w) and rotating at ( ) rad/s about its vertical axis, is

A flow is called super-sonic if the

An opening in the side of a tank or vessel such that the liquid surface with the tank is below the top edge of the opening, is called

According to Newton's law of viscosity, the shear stress on a layer of a fluid is __________ to the rate of shear strain.

Venturimeter is used to

A hemispherical tank of radius (R) containing liquid upto height (H1) has an orifice of cross-sectional area (a) at its bottom. The time required to lower the level of liquid from (H1) to (H2) will be

The force present in a moving liquid is

The force per unit length is the unit of

Kinematic viscosity is the product of dynamic viscosity and the density of the liquid.

A notch is, usually, made of a metallic plate.

In an internal mouthpiece, if the jet after contraction expands and fills up the whole mouthpiece, then the mouthpiece is said to be running free.

A channel is said to be of most economical cross-section, if

A pipe of length more than double the diameter of orifice fitted externally or internally to the orifice is called a

The pressure at a stagnation point is always low.

When an internal mouthpiece is running full, the discharge through the mouthpiece is twice the discharge when it is running free.

In two dimensional flow, the flow does not take place in a curve.

The discharge through a channel of circular section will be maximum when the depth of water is __________ the diameter of the circular channel.

When the Mach number is more than 6, the flow is called

Poise is the unit of viscosity in C.G.S. system of units.