*$_Which is not correct statement about pulverized fuel firing??

Heat release can be easily controlled

It is the best technique for burning high ash content fuel having low fusion ash

*$_A safety valve mainly used with locomotive and marine boilers is?

High steam and low water safety valve

*$_Pick up the correct statement as regards Cornish boiler and Lancashire boiler?

Cornish is fire tube and Lancashire is water tube

Cornish is water tube and Lancashire is fire tube

Cornish has two fire tubes and Lancashire has one

Lancashire has two fire tubes and Cornish has one

*/*_Water and sediment in fuel oil can be removed by?

Cooling the oil in the settling tanks

Heating the oil in the settling tanks

Cooling the oil in the settling tanks

*/*_The steam temperature with increase in load in case of a boiler fitted with radiation superheater?

First increases and then decreases

*/*_An air preheater is installed?

Between the economiser and chimney

*/*_Besides mean effective pressure, the data required to determine the indicated power of an engine include?

Specific fuel consumption, speed of rotation and torque

Piston diameter, length of stroke and calorific value of fuel

Piston diameter, specific fuel consumption and Calorific value of fuel

Piston diameter, length of stroke and speed of rotation

Specific fuel consumption, speed of rotation and torque

*/*_In regenerative air preheaters, the heat is transferred?

From a metal wall from one medium to another

From heating an intermediate material and then heating the air from this material

Heat is transferred by bleeding some gas from furnace

*/*_Adiabatic process is?

Essentially an isentropic process

*/*_The critical pressure ratio (p‚Äö√á√á/p‚Äö√á√Ö) is given by?

(p‚Äö√á√á/p‚Äö√á√Ö) = [(n - 1)/2] n + (1/n)

(p‚Äö√á√á/p‚Äö√á√Ö) = [2/(n - 1)] n/(n + 1)

(p‚Äö√á√á/p‚Äö√á√Ö) = [2/(n + 1)] n/(n-1)

(p‚Äö√á√á/p‚Äö√á√Ö) = [(n - 1)/2] n + (1/n)

(p‚Äö√á√á/p‚Äö√á√Ö) = [(n + 1)/2] n - (1/n)

*/*_The overall efficiency of thermal power plant is?

All the three above plus gas cycle efficiency

Boiler efficiency, turbine efficiency, generator efficiency

All the three above plus gas cycle efficiency

*/*_In a nozzle, the effect of super-saturation is to?

Decrease dryness fraction of steam

Decrease specific volume of steam

*/*_Primary air is the air used to?

Convert CO (formed in lower zone of furnace) into CO‚Äö√á√á at higher zone

Provide air around burners for obtaining optimum combustion

Convert CO (formed in lower zone of furnace) into CO‚Äö√á√á at higher zone

Air delivered by forced draft fan

*/*_Size of boiler tubes is specified by?

Outside diameter and inside diameter

*/*_In natural circulation type boiler,?

Water is supplied in drum and through down comers located in atmospheric condition it passes to the water wall and rises to drum in the form of mixture of water and steam

Heating takes place at bottom and the water supplied at bottom gets converted into the mixture of steam bubbles and hot water which rise to drum

Water is supplied in drum and through down comers located in atmospheric condition it passes to the water wall and rises to drum in the form of mixture of water and steam

Feed pump is employed to supplement natural circulation in water wall type furnace

Water is converted into steam in one. Pass without any recirculation

*/*_Water boils when its vapor pressure?

Equals that of the surroundings

Equals the pressure of water in the container

*/*_In an ideal impulse turbine, the?

Axial velocity at inlet is equal to that at the outlet

Absolute velocity at the inlet of moving blade is equal to that at the outlet

Relative velocity at the inlet of the moving blade is equal to that at the outlet

Axial velocity at inlet is equal to that at the outlet

Whirl velocity at inlet is equal to that at the outlet

*/*_In order to compare the capacity of boilers, the feed water temperature and working pressure are taken as?

100¬¨‚àûC and 1.1 bar pressure

50¬¨‚àûC and normal atmospheric pressure

50¬¨‚àûC and 1.1 bar pressure

100¬¨‚àûC and normal atmospheric pressure

100¬¨‚àûC and 1.1 bar pressure

*/*_The number of drums in Benson steam generator is?

One steam drum and one water drum

*/*_Over fire burning is the phenomenon of?

Burning CO and unburnt in upper zone of furnace by supplying more air

*/*_For combustion of a fuel, following is essential?

O‚Äö√á√á to support combustion

*/*_Bomb calorimeter is used to determine?

Lower calorific value at constant volume

Higher calorific value at constant volume

Lower calorific value at constant volume

Higher calorific value at constant pressure

Lower calorific value at constant pressure

*/*_The change in internal energy in steam engines equals to?

Work done during the Rankine cycle

Work done during adiabatic expansion

*/*_Desecration of feed water is carried out because it reduces?

Cavitation of boiler feed pumps

*/*_Locomotive type' boiler is?

Horizontal multi-tubular water tube boiler

Water wall enclosed furnace type

Vertical tubular fire tube type

Horizontal multi-tubular fire tube type

*/*_The clearance in the engine cylinder?

Increases the mean effective pressure

Decreases the efficiency of the engine

760 + Mcqs in Steam Boilers, Engines, Nozzles And Turbines Page 7 McqOptions

301.	*$_The process of draining steam from the turbine, at certain points during its expansion and using this steam for heating the feed water in feed water heaters and then supplying it to the boiler is known as?
A.	Regenerative heating
B.	Reheating of steam
C.	Bleeding
D.	None of these
Answer» D. None of these

302.	*$_The fusible plug in small boilers is located?
A.	In the drum
B.	In the fire tubes
C.	Above steam dome
D.	Over the combustion chamber
Answer» E.

303.	*$_The diameter of superheated tubes in a locomotive boiler is?
A.	13 mm
B.	31 mm
C.	130 mm
D.	230 mm
Answer» D. 230 mm

304.	*$_When the cross-section of a nozzle __________ continuously from entrance to exit, it is called a convergent nozzle.?
A.	Increases
B.	Decreases
C.	Remain same
D.	None of these
Answer» C. Remain same

305.	*$_Lancashire boiler is used where working pressure and power required are?
A.	Low
B.	Moderate
C.	High
D.	None of these
Answer» C. High

306.	*$_Which is not correct statement about pulverized fuel firing??
A.	High burning rate is possible
B.	Heat release can be easily controlled
C.	Fuel burns economically
D.	It is the best technique for burning high ash content fuel having low fusion ash
Answer» E.

307.	*$_All steam engines work on?
A.	Zeroth law of thermodynamics
B.	First law of thermodynamics
C.	Second law of thermodynamics
D.	None of these
Answer» D. None of these

308.	*$_A safety valve mainly used with locomotive and marine boilers is?
A.	Lever safety valve
B.	Dead weight safety valve
C.	High steam and low water safety valve
D.	Spring loaded safety valve
Answer» E.

309.	*$_Pick up the correct statement as regards Cornish boiler and Lancashire boiler?
A.	Cornish is fire tube and Lancashire is water tube
B.	Cornish is water tube and Lancashire is fire tube
C.	Cornish has two fire tubes and Lancashire has one
D.	Lancashire has two fire tubes and Cornish has one
Answer» E.

310.	*$_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

311.	/_A _________ in a boiler is used to put off fire in the furnace of the boiler when the level of water in the boiler falls to an unsafe limit.?
A.	Blow off cock
B.	Fusible plug
C.	Stop valve
D.	Safety valve
Answer» C. Stop valve

314.	/_The chimney draught varies with?
A.	Climatic conditions
B.	Temperature of furnace gases
C.	Height of chimney
D.	All of these
Answer» E.

319.	/_The biggest size of thermal power unit operating in India is?
A.	30 MW
B.	60 MW
C.	100 MW
D.	500 MW
Answer» E.

335.	/_A condenser where circulating water flows through tubes which are surrounded by steam, in known as?
A.	Surface condenser
B.	Jet condenser
C.	Barometric condenser
D.	Evaporative condenser
Answer» B. Jet condenser

337.	/_When the nozzle operates with the maximum mass flow, the nozzle is said to be?
A.	Choked
B.	Under-damping
C.	Over-damping
D.	None of these
Answer» B. Under-damping

312.	/_Water and sediment in fuel oil can be removed by?
A.	Heating the oil in the settling tanks
B.	Cooling the oil in the settling tanks
C.	Burning the oil
D.	Suspension
Answer» B. Cooling the oil in the settling tanks

313.	/_The efficiency of the plant __________ with the mechanical draught.?
A.	Increases
B.	Decreases
C.	Remains constant
D.	None of these
Answer» B. Decreases

315.	/_The ratio of the workdone on the blades to the energy supplied to the blades, is called?
A.	Blading efficiency
B.	Nozzle efficiency
C.	Gross or stage efficiency
D.	Mechanical efficiency
Answer» B. Nozzle efficiency

316.	/_The steam temperature with increase in load in case of a boiler fitted with radiation superheater?
A.	Increases
B.	Decreases
C.	Remain unaffected
D.	First increases and then decreases
Answer» C. Remain unaffected

317.	/_An impulse turbine as compared to a reaction turbine, for a given power has _________ row of blades.?
A.	Equal
B.	Less
C.	More
D.	None of these
Answer» D. None of these

318.	/_An air preheater is installed?
A.	Before the economiser
B.	Before the superheater
C.	Between the economiser and chimney
D.	None of these
Answer» D. None of these

320.	/_Besides mean effective pressure, the data required to determine the indicated power of an engine include?
A.	Piston diameter, length of stroke and calorific value of fuel
B.	Piston diameter, specific fuel consumption and Calorific value of fuel
C.	Piston diameter, length of stroke and speed of rotation
D.	Specific fuel consumption, speed of rotation and torque
Answer» D. Specific fuel consumption, speed of rotation and torque

321.	/_In regenerative air preheaters, the heat is transferred?
A.	From a metal wall from one medium to another
B.	From heating an intermediate material and then heating the air from this material
C.	By direct mixing
D.	Heat is transferred by bleeding some gas from furnace
Answer» C. By direct mixing

322.	/_Adiabatic process is?
A.	Essentially an isentropic process
B.	Non-heat transfer process
C.	Reversible process
D.	Constant temperature process
Answer» C. Reversible process

323.	/_The critical pressure ratio (p‚Äö√á√á/p‚Äö√á√Ö) is given by?
A.	(p‚Äö√á√á/p‚Äö√á√Ö) = [2/(n - 1)] n/(n + 1)
B.	(p‚Äö√á√á/p‚Äö√á√Ö) = [2/(n + 1)] n/(n-1)
C.	(p‚Äö√á√á/p‚Äö√á√Ö) = [(n - 1)/2] n + (1/n)
D.	(p‚Äö√á√á/p‚Äö√á√Ö) = [(n + 1)/2] n - (1/n)
Answer» C. (p‚Äö√á√á/p‚Äö√á√Ö) = [(n - 1)/2] n + (1/n)

Explore topic-wise MCQs in Mechanical Engineering.

*$_The process of draining steam from the turbine, at certain points during its expansion and using this steam for heating the feed water in feed water heaters and then supplying it to the boiler is known as?

*$_The fusible plug in small boilers is located?

*$_The diameter of superheated tubes in a locomotive boiler is?

*$_When the cross-section of a nozzle __________ continuously from entrance to exit, it is called a convergent nozzle.?

*$_Lancashire boiler is used where working pressure and power required are?

*$_Which is not correct statement about pulverized fuel firing??

*$_All steam engines work on?

*$_A safety valve mainly used with locomotive and marine boilers is?

*$_Pick up the correct statement as regards Cornish boiler and Lancashire boiler?

*$_The maximum heat loss is a boiler occurs due to?

*/*_A _________ in a boiler is used to put off fire in the furnace of the boiler when the level of water in the boiler falls to an unsafe limit.?

*/*_Water and sediment in fuel oil can be removed by?

*/*_The efficiency of the plant __________ with the mechanical draught.?

*/*_The chimney draught varies with?

*/*_The ratio of the workdone on the blades to the energy supplied to the blades, is called?

*/*_The steam temperature with increase in load in case of a boiler fitted with radiation superheater?

*/*_An impulse turbine as compared to a reaction turbine, for a given power has _________ row of blades.?

*/*_An air preheater is installed?

*/*_The biggest size of thermal power unit operating in India is?

*/*_Besides mean effective pressure, the data required to determine the indicated power of an engine include?

*/*_In regenerative air preheaters, the heat is transferred?

*/*_Adiabatic process is?

*/*_The critical pressure ratio (p‚Äö√á√á/p‚Äö√á√Ö) is given by?

*/*_The overall efficiency of thermal power plant is?

*/*_In a nozzle, the effect of super-saturation is to?

*/*_Primary air is the air used to?

*/*_The water tubes in a simple vertical boiler are?

*/*_The diameter of Cornish boiler is of the order of?

*/*_Size of boiler tubes is specified by?

*/*_In natural circulation type boiler,?

*/*_Water boils when its vapor pressure?

*/*_In an ideal impulse turbine, the?

*/*_In order to compare the capacity of boilers, the feed water temperature and working pressure are taken as?

*/*_The number of drums in Benson steam generator is?

*/*_A condenser where circulating water flows through tubes which are surrounded by steam, in known as?

*/*_Over fire burning is the phenomenon of?

*/*_When the nozzle operates with the maximum mass flow, the nozzle is said to be?

*/*_The actual power generated in the engine cylinder is called?

*/*_For combustion of a fuel, following is essential?

*/*_Bomb calorimeter is used to determine?

*/*_In which of the following boilers, the draught in furnace is increased by utilising exhaust steam from engine?

*/*_The change in internal energy in steam engines equals to?

*/*_The diameter of fire tube of Cornish boiler compared to its shell is?

*/*_Hard coke is used in?

*/*_The reheat factor depends upon?

*/*_Desecration of feed water is carried out because it reduces?

*/*_Locomotive type' boiler is?

*/*_The clearance in the engine cylinder?

*/*_The ratio of the work-done on the blades per kg of steam to the total energy supplied per stage per kg of steam is called?

*/*_Steam turbines may be classified according to?

/_A _________ in a boiler is used to put off fire in the furnace of the boiler when the level of water in the boiler falls to an unsafe limit.?

/_Water and sediment in fuel oil can be removed by?

/_The efficiency of the plant __________ with the mechanical draught.?

/_The chimney draught varies with?

/_The ratio of the workdone on the blades to the energy supplied to the blades, is called?

/_The steam temperature with increase in load in case of a boiler fitted with radiation superheater?

/_An impulse turbine as compared to a reaction turbine, for a given power has _________ row of blades.?

/_An air preheater is installed?

/_The biggest size of thermal power unit operating in India is?

/_Besides mean effective pressure, the data required to determine the indicated power of an engine include?

/_In regenerative air preheaters, the heat is transferred?

/_Adiabatic process is?

/_The critical pressure ratio (p‚Äö√á√á/p‚Äö√á√Ö) is given by?

/_The overall efficiency of thermal power plant is?

/_In a nozzle, the effect of super-saturation is to?

/_Primary air is the air used to?

/_The water tubes in a simple vertical boiler are?

/_The diameter of Cornish boiler is of the order of?

/_Size of boiler tubes is specified by?

/_In natural circulation type boiler,?

/_Water boils when its vapor pressure?

/_In an ideal impulse turbine, the?

/_In order to compare the capacity of boilers, the feed water temperature and working pressure are taken as?

/_The number of drums in Benson steam generator is?

/_A condenser where circulating water flows through tubes which are surrounded by steam, in known as?

/_Over fire burning is the phenomenon of?

/_When the nozzle operates with the maximum mass flow, the nozzle is said to be?

/_The actual power generated in the engine cylinder is called?

/_For combustion of a fuel, following is essential?

/_Bomb calorimeter is used to determine?

/_In which of the following boilers, the draught in furnace is increased by utilising exhaust steam from engine?

/_The change in internal energy in steam engines equals to?

/_The diameter of fire tube of Cornish boiler compared to its shell is?

/_Hard coke is used in?

/_The reheat factor depends upon?

/_Desecration of feed water is carried out because it reduces?

/_Locomotive type' boiler is?

/_The clearance in the engine cylinder?

/_The ratio of the work-done on the blades per kg of steam to the total energy supplied per stage per kg of steam is called?

/_Steam turbines may be classified according to?

324.	/_The overall efficiency of thermal power plant is?
A.	Boiler efficiency, turbine efficiency, generator efficiency
B.	All the three above plus gas cycle efficiency
C.	Carnot cycle efficiency
D.	Regenerative cycle efficiency
Answer» B. All the three above plus gas cycle efficiency

325.	/_In a nozzle, the effect of super-saturation is to?
A.	Decrease dryness fraction of steam
B.	Decrease specific volume of steam
C.	Increase the entropy
D.	Increase the heat drop
Answer» D. Increase the heat drop

326.	/_Primary air is the air used to?
A.	Provide air around burners for obtaining optimum combustion
B.	Transport and dry the coal
C.	Convert CO (formed in lower zone of furnace) into CO‚Äö√á√á at higher zone
D.	Air delivered by forced draft fan
Answer» C. Convert CO (formed in lower zone of furnace) into CO‚Äö√á√á at higher zone

327.	/_The water tubes in a simple vertical boiler are?
A.	Horizontal
B.	Vertical
C.	Inclined
D.	None of these
Answer» D. None of these

328.	/_The diameter of Cornish boiler is of the order of?
A.	12 m
B.	1.52.5 m
C.	23 m
D.	2.53.5 m
Answer» B. 1.52.5 m

329.	/_Size of boiler tubes is specified by?
A.	Mean diameter and thickness
B.	Inside diameter and thickness
C.	Outside diameter and thickness
D.	Outside diameter and inside diameter
Answer» D. Outside diameter and inside diameter

330.	/_In natural circulation type boiler,?
A.	Heating takes place at bottom and the water supplied at bottom gets converted into the mixture of steam bubbles and hot water which rise to drum
B.	Water is supplied in drum and through down comers located in atmospheric condition it passes to the water wall and rises to drum in the form of mixture of water and steam
C.	Feed pump is employed to supplement natural circulation in water wall type furnace
D.	Water is converted into steam in one. Pass without any recirculation
Answer» B. Water is supplied in drum and through down comers located in atmospheric condition it passes to the water wall and rises to drum in the form of mixture of water and steam

331.	/_Water boils when its vapor pressure?
A.	Equals that of the surroundings
B.	Equals 760 mm of mercury
C.	Equals to atmospheric pressure
D.	Equals the pressure of water in the container
Answer» B. Equals 760 mm of mercury

332.	/_In an ideal impulse turbine, the?
A.	Absolute velocity at the inlet of moving blade is equal to that at the outlet
B.	Relative velocity at the inlet of the moving blade is equal to that at the outlet
C.	Axial velocity at inlet is equal to that at the outlet
D.	Whirl velocity at inlet is equal to that at the outlet
Answer» C. Axial velocity at inlet is equal to that at the outlet

333.	/_In order to compare the capacity of boilers, the feed water temperature and working pressure are taken as?
A.	50¬¨‚àûC and normal atmospheric pressure
B.	50¬¨‚àûC and 1.1 bar pressure
C.	100¬¨‚àûC and normal atmospheric pressure
D.	100¬¨‚àûC and 1.1 bar pressure
Answer» D. 100¬¨‚àûC and 1.1 bar pressure