__The latent heat of steam at pressures greater than atmospheric in comparison to latent heat at atmospheric pressure is__

May be less or more depending on temperature

__The object of producing draught in a boiler is__

To provide an adequate supply of air for the fuel combustion

To exhaust the gases of combustion from the combustion chamber

To discharge the gases of combustion to the atmosphere through the chimney

__The equivalent evaporation is defined as__

The evaporation of 15.653 kg of water per hour from and at 100¬¨‚àûC

The ratio of heat actually used in producing the steam to the heat liberated in the furnace

The amount of water evaporated or steam produced in kg per kg of fuel burnt

The amount of water evaporated from and at 100¬¨‚àûC into dry and saturated steam

The evaporation of 15.653 kg of water per hour from and at 100¬¨‚àûC

__The relative efficiency is defined as the__

Ratio of brake power to the indicated power

Ratio of thermal efficiency to Rankine efficiency

Ratio of brake power to the indicated power

Ratio of heat equivalent to indicated power to the energy supplied in steam

Product of thermal efficiency and Rankine efficiency

_Pick up the wrong statement about critical condition of steam$?

Specific volume of steam and liquid is same

This is the maximum pressure limit

_The function of injector used in small capacity boilers is to$?

Add make up water in the system

Inject chemical solution in feed pump

Pump water, similar to boiler feed pump

Add make up water in the system

_The efficiency of a boiler is defined as$?

Ratio of the mass of steam produced to the mass of total water supplied in a given time

Ratio of heat actually used in producing steam to the heat liberated in the furnace

Ratio of the mass of steam produced to the mass of total water supplied in a given time

Ratio of the heat liberated in the furnace to the heat actually used in producing steam

_Incomplete combustion can be best judged by$?

Measuring temperature of flue gases at exit of furnace

Measuring carbon monoxide in flue gases

Measuring temperature of flue gases at exit of furnace

_In water tube boilers$?

The flames and hot gases pass through the tubes which are surrounded by water

Water passes through the tubes which are surrounded by flames and hot gases

The flames and hot gases pass through the tubes which are surrounded by water

_The purpose of governing in steam turbines is to$?

Maintain the speed of the turbine

Reheat the steam and improve its quality

Completely balance against end thrust

_The function of a safety valve is$?

To indicate the water level inside the boiler to an observer

To blow off steam when the pressure of steam inside the boiler exceeds the working pressure

To indicate the water level inside the boiler to an observer

To measure pressure of steam inside the steam boiler

_The shell of the Cochran boiler is made hemispherical$?

To give maximum space and strength

To withstand the pressure of steam inside the boiler

_The steam leaves the nozzle at a$?

High pressure and a low velocity

High pressure and a high velocity

Low pressure and a low velocity

Low pressure and a high velocity

_In a reaction turbine when the degree of reaction is zero, then there is$?

Maximum heat drop in moving blades

Maximum heat drop in fixed blades

_De-Laval turbines are mostly used$?

For small power purposes and low speeds

For small power purposes and high speeds

_In a single acting steam engine$?

The steam is admitted, in turn, on both sides of the piston and one working stroke is produced during each revolution of the crankshaft

The steam is admitted on one side of the piston and one working stroke is produced during each revolution of the crankshaft

The steam is admitted, in turn, on both sides of the piston and one working stroke is produced during each revolution of the crankshaft

The steam is admitted on one side of the piston and two working strokes are produced during each revolution of the crankshaft

The steam is admitted, in turn, on both sides of the piston and two working strokes are produced during each revolution of the crankshaft

_A condenser in a steam power plant$?

Increases expansion ratio of steam

Reduces temperature of exhaust steam

_The aim of a compound steam engine is$?

To reduce the ratio of expansion in each cylinder

To reduce the temperature range in each cylinder

760 + Mcqs in Steam Boilers, Engines, Nozzles And Turbines Page 11 McqOptions

501.	__The numbers of fire tubes in a Cochran boiler are__
A.	75
B.	115
C.	165
D.	225
Answer» D. 225

Discussion

502.	__The latent heat of steam at pressures greater than atmospheric in comparison to latent heat at atmospheric pressure is__
A.	Less
B.	More
C.	Equal
D.	May be less or more depending on temperature
Answer» B. More

Discussion

503.	__The diameter of internal flue tubes of a Lancashire boiler is about _________ that of its shell.__
A.	One-fourth
B.	One-third
C.	Two-fifth
D.	One-half
Answer» D. One-half

Discussion

504.	__Which of the following are boiler accessories?__
A.	Economizer
B.	Superheater
C.	Both (A) and (B)
D.	None of these
Answer» D. None of these

Discussion

505.	__The object of producing draught in a boiler is__
A.	To provide an adequate supply of air for the fuel combustion
B.	To exhaust the gases of combustion from the combustion chamber
C.	To discharge the gases of combustion to the atmosphere through the chimney
D.	All of the above
Answer» E.

Discussion

506.	__The equivalent evaporation is defined as__
A.	The ratio of heat actually used in producing the steam to the heat liberated in the furnace
B.	The amount of water evaporated or steam produced in kg per kg of fuel burnt
C.	The amount of water evaporated from and at 100¬¨‚àûC into dry and saturated steam
D.	The evaporation of 15.653 kg of water per hour from and at 100¬¨‚àûC
Answer» D. The evaporation of 15.653 kg of water per hour from and at 100¬¨‚àûC

Discussion

507.	__Which of the following varieties of coals is mostly used in steam boilers?__
A.	Non-coking bituminous coal
B.	Brown coal
C.	Peat
D.	None of the above
Answer» E.

Discussion

508.	__At very low temperature, the melting and boiling temperatures become equal. This temperature is__
A.	373¬¨‚àûK
B.	273.16¬¨‚àûK
C.	303¬¨‚àûK
D.	0¬¨‚àûK
Answer» C. 303¬¨‚àûK

Discussion

509.	__The relative efficiency is defined as the__
A.	Ratio of thermal efficiency to Rankine efficiency
B.	Ratio of brake power to the indicated power
C.	Ratio of heat equivalent to indicated power to the energy supplied in steam
D.	Product of thermal efficiency and Rankine efficiency
Answer» B. Ratio of brake power to the indicated power

Discussion

510.	_When the circulation of water, in a boiler, is by convection currents which are set up during the heating of water, then the boiler is known as$?
A.	Internally fired boiler
B.	Externally fired boiler
C.	Natural circulation boiler
D.	Forced circulation boiler
Answer» D. Forced circulation boiler

Discussion

511.	_The diameter of a cylindrical shell of a Scotch marine boiler varies from$?
A.	1.5 to 2 m
B.	2.5 to 3.5 m
C.	3.5 to 4.5 m
D.	None of these
Answer» C. 3.5 to 4.5 m

Discussion

512.	_The length of shell of a Locomotive boiler is$?
A.	1 m
B.	2 m
C.	3 m
D.	4 m
Answer» E.

Discussion

513.	_Pick up the wrong statement about critical condition of steam$?
A.	Latent heat is zero
B.	Liquid directly becomes steam
C.	Specific volume of steam and liquid is same
D.	This is the maximum pressure limit
Answer» E.

Discussion

514.	_Throttle governing of steam engines is a method of controlling the engine output by varying$?
A.	Volume of intake steam
B.	Pressure of intake steam
C.	Temperature of intake steam
D.	All of these
Answer» C. Temperature of intake steam

Discussion

515.	_The function of injector used in small capacity boilers is to$?
A.	Create vacuum
B.	Inject chemical solution in feed pump
C.	Pump water, similar to boiler feed pump
D.	Add make up water in the system
Answer» D. Add make up water in the system

Discussion

516.	_Which of the following substance will have same percentage in both proximate and ultimate analysis?$?
A.	Ash
B.	Volatile matter
C.	Moisture
D.	Hydrogen
Answer» B. Volatile matter

Discussion

517.	_The fire tubes in a Scotch marine boiler are$?
A.	Horizontal
B.	Vertical
C.	Inclined
D.	None of these
Answer» B. Vertical

Discussion

518.	_Thermal efficiency of well maintained boiler will be of the order$?
A.	40 %
B.	50 %
C.	75 %
D.	90 %
Answer» E.

Discussion

519.	_The efficiency of a boiler is defined as$?
A.	Ratio of heat actually used in producing steam to the heat liberated in the furnace
B.	Ratio of the mass of steam produced to the mass of total water supplied in a given time
C.	Ratio of the heat liberated in the furnace to the heat actually used in producing steam
D.	None of the above
Answer» B. Ratio of the mass of steam produced to the mass of total water supplied in a given time

Discussion

520.	_The mechanical draught _________ with the amount of smoke.$?
A.	Increases
B.	Decreases
C.	Does not effect
D.	None of these
Answer» C. Does not effect

Discussion

521.	_Film boiling occurs at$?
A.	Very low pressure
B.	Atmospheric pressures
C.	Medium pressures
D.	Very high pressures
Answer» E.

Discussion

522.	_Lancashire boiler is$?
A.	Stationary fire tube boiler
B.	Internally fired boiler
C.	Horizontal boiler
D.	All of these
Answer» E.

Discussion

523.	_The critical pressure ratio for initially dry saturated steam is$?
A.	0.546
B.	0.577
C.	0.582
D.	0.601
Answer» C. 0.582

Discussion

524.	_Incomplete combustion can be best judged by$?
A.	Smoky chimney exit
B.	Excess air in flue gases
C.	Measuring carbon monoxide in flue gases
D.	Measuring temperature of flue gases at exit of furnace
Answer» D. Measuring temperature of flue gases at exit of furnace

Discussion

525.	_When the total heat of steam is h kJ/kg and the sensible heat of feed water is hf1 kJ/kg, then the factor of evaporation is given by$?
A.	(h - hf1)/2257
B.	(h + hf1)/2257
C.	(h ‚àö√≥ hf1)/2257
D.	None of these
Answer» B. (h + hf1)/2257

Discussion

526.	_The ratio of the volume at cut-off to the swept volume is called$?
A.	Cut-off ratio
B.	Expansion ratio
C.	Clearance ratio
D.	None of these
Answer» B. Expansion ratio

Discussion

527.	_In water tube boilers$?
A.	Water passes through the tubes which are surrounded by flames and hot gases
B.	The flames and hot gases pass through the tubes which are surrounded by water
C.	Forced circulation takes place
D.	None of these
Answer» B. The flames and hot gases pass through the tubes which are surrounded by water

Discussion

528.	_The purpose of governing in steam turbines is to$?
A.	Maintain the speed of the turbine
B.	Reduce the effective heat drop
C.	Reheat the steam and improve its quality
D.	Completely balance against end thrust
Answer» B. Reduce the effective heat drop

Discussion

529.	_The ratio of the useful heat drop to the isentropic heat drop is called$?
A.	Condenser efficiency
B.	Nozzle efficiency
C.	Boiler efficiency
D.	Vacuum efficiency
Answer» C. Boiler efficiency

Discussion

530.	_The function of a safety valve is$?
A.	To blow off steam when the pressure of steam inside the boiler exceeds the working pressure
B.	To indicate the water level inside the boiler to an observer
C.	To measure pressure of steam inside the steam boiler
D.	None of the above
Answer» B. To indicate the water level inside the boiler to an observer

Discussion

531.	_The fire tubes in a Locomotive boiler has __________ diameter.$?
A.	4.75 mm
B.	5.47 mm
C.	7.45 mm
D.	47.5 mm
Answer» E.

Discussion

532.	_The shell of the Cochran boiler is made hemispherical$?
A.	To give maximum space and strength
B.	To withstand the pressure of steam inside the boiler
C.	Both (A) and (B)
D.	None of the above
Answer» D. None of the above

Discussion

533.	_The steam leaves the nozzle at a$?
A.	High pressure and a low velocity
B.	High pressure and a high velocity
C.	Low pressure and a low velocity
D.	Low pressure and a high velocity
Answer» E.

Discussion

534.	_The coal requirement per kW hour generation in the thermal power plant is of the order of$?
A.	0.1 to 0.2 kg
B.	0.2 to 0.4 kg
C.	0.6 to 0.8 kg
D.	1.0 to 1.5 kg
Answer» D. 1.0 to 1.5 kg

Discussion

535.	_In a reaction turbine when the degree of reaction is zero, then there is$?
A.	No heat drop in moving blades
B.	No heat drop in fixed blades
C.	Maximum heat drop in moving blades
D.	Maximum heat drop in fixed blades
Answer» B. No heat drop in fixed blades

Discussion

536.	_The length of Cornish boiler is of the order of$?
A.	24 m
B.	35 m
C.	57.5 m
D.	79 m
Answer» D. 79 m

Discussion

537.	_De-Laval turbines are mostly used$?
A.	Where low speeds are required
B.	For small power purposes and low speeds
C.	For large power purposes
D.	For small power purposes and high speeds
Answer» E.

Discussion

538.	_In a single acting steam engine$?
A.	The steam is admitted on one side of the piston and one working stroke is produced during each revolution of the crankshaft
B.	The steam is admitted, in turn, on both sides of the piston and one working stroke is produced during each revolution of the crankshaft
C.	The steam is admitted on one side of the piston and two working strokes are produced during each revolution of the crankshaft
D.	The steam is admitted, in turn, on both sides of the piston and two working strokes are produced during each revolution of the crankshaft
Answer» B. The steam is admitted, in turn, on both sides of the piston and one working stroke is produced during each revolution of the crankshaft

Discussion

539.	_In impulse turbines, when friction is neglected, the relative velocity of steam at outlet tip of the blade is _________ the relative velocity of steam at inlet tip of the blade.$?
A.	Equal to
B.	Less than
C.	Greater than
D.	None of these
Answer» B. Less than

Discussion

540.	_The ratio of the energy required to produce the artificial draught (expressed in meters head or J/kg of flue gas) to the mechanical equivalent of extra heat carried away per kg of flue gases due to natural draught, is known as$?
A.	Efficiency of the boiler
B.	Efficiency of the chimney
C.	Efficiency of the fan
D.	Power of the boiler
Answer» C. Efficiency of the fan

Discussion

541.	_A condenser in a steam power plant$?
A.	Increases expansion ratio of steam
B.	Reduces back pressure of steam
C.	Reduces temperature of exhaust steam
D.	All of these
Answer» E.

Discussion

542.	_With increase in load, radiant superheater has$?
A.	Drooping characteristic
B.	Linear characteristic
C.	Rising characteristic
D.	Flat characteristic
Answer» B. Linear characteristic

Discussion

543.	_If the critical pressure ratio for steam is 0.546, then the steam is initially$?
A.	Wet steam
B.	Dry saturated steam
C.	Superheated steam
D.	None of these
Answer» D. None of these

Discussion

544.	_The draught (in mm of water), for maximum discharge of flue gases through the chimney, is given by (where H = Height of the chimney in meters, and T1 = Absolute temperature of air outside the chimney in K)$?
A.	T1 /88.25H
B.	88.25H/T1
C.	T1 /176.5H
D.	176.5H/T1
Answer» E.

Discussion

545.	_Hard coke is produced by carburization of coal at$?
A.	Atmospheric temperature
B.	500-600¬¨‚àûC
C.	700-850¬¨‚àûC
D.	950-1100¬¨‚àûC
Answer» E.

Discussion

546.	_The specific heat of superheated steam in kcal/kg is generally of the order of$?
A.	0.1
B.	0.3
C.	0.5
D.	0.8
Answer» D. 0.8

Discussion

547.	_The pressure at which latent heat of vaporisation of water is zero, is$?
A.	Below atmospheric pressure
B.	1 kg/cm¬¨‚â§
C.	100 kg/cm¬¨‚â§
D.	225.6 kg/cm¬¨‚â§
Answer» E.

Discussion

548.	_The turbine blades are$?
A.	Straight
B.	Circular
C.	Curved
D.	None of these
Answer» D. None of these

Discussion

549.	_Latent heat of dry steam at atmospheric pressure is equal to$?
A.	539 kcal/ kg
B.	539 BTU/ lb
C.	427 kcal/ kg
D.	100 kcal/ kg
Answer» B. 539 BTU/ lb

Discussion

550.	_The aim of a compound steam engine is$?
A.	To reduce the ratio of expansion in each cylinder
B.	To reduce the length of stroke
C.	To reduce the temperature range in each cylinder
D.	All of the above
Answer» E.

Discussion

Explore topic-wise MCQs in Mechanical Engineering.

__The numbers of fire tubes in a Cochran boiler are__

__The latent heat of steam at pressures greater than atmospheric in comparison to latent heat at atmospheric pressure is__

__The diameter of internal flue tubes of a Lancashire boiler is about _________ that of its shell.__

__Which of the following are boiler accessories?__

__The object of producing draught in a boiler is__

__The equivalent evaporation is defined as__

__Which of the following varieties of coals is mostly used in steam boilers?__

__At very low temperature, the melting and boiling temperatures become equal. This temperature is__

__The relative efficiency is defined as the__

_When the circulation of water, in a boiler, is by convection currents which are set up during the heating of water, then the boiler is known as$?

_The diameter of a cylindrical shell of a Scotch marine boiler varies from$?

_The length of shell of a Locomotive boiler is$?

_Pick up the wrong statement about critical condition of steam$?

_Throttle governing of steam engines is a method of controlling the engine output by varying$?

_The function of injector used in small capacity boilers is to$?

_Which of the following substance will have same percentage in both proximate and ultimate analysis?$?

_The fire tubes in a Scotch marine boiler are$?

_Thermal efficiency of well maintained boiler will be of the order$?

_The efficiency of a boiler is defined as$?

_The mechanical draught _________ with the amount of smoke.$?

_Film boiling occurs at$?

_Lancashire boiler is$?

_The critical pressure ratio for initially dry saturated steam is$?

_Incomplete combustion can be best judged by$?

_When the total heat of steam is h kJ/kg and the sensible heat of feed water is hf1 kJ/kg, then the factor of evaporation is given by$?

_The ratio of the volume at cut-off to the swept volume is called$?

_In water tube boilers$?

_The purpose of governing in steam turbines is to$?

_The ratio of the useful heat drop to the isentropic heat drop is called$?

_The function of a safety valve is$?

_The fire tubes in a Locomotive boiler has __________ diameter.$?

_The shell of the Cochran boiler is made hemispherical$?

_The steam leaves the nozzle at a$?

_The coal requirement per kW hour generation in the thermal power plant is of the order of$?

_In a reaction turbine when the degree of reaction is zero, then there is$?

_The length of Cornish boiler is of the order of$?

_De-Laval turbines are mostly used$?

_In a single acting steam engine$?

_In impulse turbines, when friction is neglected, the relative velocity of steam at outlet tip of the blade is _________ the relative velocity of steam at inlet tip of the blade.$?

_The ratio of the energy required to produce the artificial draught (expressed in meters head or J/kg of flue gas) to the mechanical equivalent of extra heat carried away per kg of flue gases due to natural draught, is known as$?

_A condenser in a steam power plant$?

_With increase in load, radiant superheater has$?

_If the critical pressure ratio for steam is 0.546, then the steam is initially$?

_The draught (in mm of water), for maximum discharge of flue gases through the chimney, is given by (where H = Height of the chimney in meters, and T1 = Absolute temperature of air outside the chimney in K)$?

_Hard coke is produced by carburization of coal at$?

_The specific heat of superheated steam in kcal/kg is generally of the order of$?

_The pressure at which latent heat of vaporisation of water is zero, is$?

_The turbine blades are$?

_Latent heat of dry steam at atmospheric pressure is equal to$?

_The aim of a compound steam engine is$?

The numbers of fire tubes in a Cochran boiler are

The latent heat of steam at pressures greater than atmospheric in comparison to latent heat at atmospheric pressure is

The diameter of internal flue tubes of a Lancashire boiler is about _____ that of its shell.

Which of the following are boiler accessories?

The object of producing draught in a boiler is

The equivalent evaporation is defined as

Which of the following varieties of coals is mostly used in steam boilers?

At very low temperature, the melting and boiling temperatures become equal. This temperature is

The relative efficiency is defined as the