Electricity Generation ( Power Plant Engineering ) MCQs – Mechanical Engineering MCQs
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Mechanical Engineering MCQs – Electricity Generation ( Power Plant Engineering ) MCQs
The most occurred mcqs of ( ) in past papers. Past papers of Electricity Generation ( Power Plant Engineering ) Mcqs. Past papers of Electricity Generation ( Power Plant Engineering ) Mcqs . Mcqs are the necessary part of any competitive / job related exams. The Mcqs having specific numbers in any written test. It is therefore everyone have to learn / remember the related Electricity Generation ( Power Plant Engineering ) Mcqs. The Important series of Electricity Generation ( Power Plant Engineering ) Mcqs are given below:
Steam Turbines Basics – I
1. A steam turbine converts the output from a steam generator into ____________
a) Shaft work
b) Turbine work
c) Mechanical work
d) None of the mentioned
Answer: a
Explanation: A steam turbine is a device that converts the energy of high-pressure, high-temperature steam supplied by a steam generator into shaft work.
2. The energy conversion occurring in a steam turbine is a ______ step process.
a) 1
b) 2
c) 3
d) 4
Answer: b
Explanation: The high pressure steam first expands in a nozzle, gains velocity & then loses this velocity when it impinges on the blades.
3. A steam turbine is basically an assemblage of ____________
a) nozzle & condenser
b) blades & condenser
c) nozzle & blades
d) nozzle & fans
Answer: c
Explanation: A steam turbine is a device that converts the energy of high-pressure, high-temperature steam supplied by a steam generator into shaft work. The high pressure steam first expands in a nozzle, gains velocity & then loses this velocity when it impinges on the blades.
4. Depending on whether the back pressure is below or equal to the atmospheric pressure, how many types of turbines do exist?
a) 1
b) 2
c) 3
d) 4
Answer: b
Explanation: Depending on whether the back pressure is below or equal to the atmospheric pressure, there are two types of turbines that exist- condensing & non-condensing turbines.
5. The overall steam turbine generator arrangement of a power plant is designated as ________ compound on the basis of shaft orientation.
a) tandem
b) cross
c) tandem & cross
d) none of the mentioned
Answer: c
Explanation: The overall steam turbine generator arrangement of a power plant is designated as tandem or cross-compound on the basis of shaft orientation.
6. A ______ is a duct through which velocity of a fluid increases at the expense of pressure.
a) orifice
b) nozzle
c) jet
d) diffuser
Answer: b
Explanation: A nozzle is a duct through which the velocity of a fluid increases at the expense of pressure.
7. A duct which decreases the velocity of fluid & causes a corresponding increase in pressure is called?
a) nozzle
b) diffuser
c) jet
d) orifice
Answer: b
Explanation: A duct which decreases the velocity of fluid & causes a corresponding increase in pressure is called a diffuser.
8. A regenerative steam cycle renders ____________
a) decreased work output per unit mass of steam
b) increased thermal efficiency
c) increased work output per unit mass of steam
d) decreased work output per unit mass of steam as well as increased thermal efficiency
Answer: d
Explanation: The decreased work output per unit mass of steam as well as increased thermal efficiency.
9. The reheat factor is the ratio of the ____________
a) total useful heat drop to the total isentropic heat drop
b) cumulative heat drop to the isentropic heat drop
c) isentropic heat drop to the heat supplied
d) none of the mentioned
Answer: b
Explanation: The ratio of cumulative heat drop to the isentropic heat drop is called the reheat factor.
10. Thermal equilibrium means that the flow of steam is ____________
a) hyperbolic
b) isothermal
c) isentropic
d) polytropic
Answer: c
Explanation: When the steam flow is isentropic it is thermal equilibrium condition.
Steam Turbines Basics – II
1. The ratio of the work done on the blades to the energy supplied to the blades is called ____________
a) gross or stage efficiency
b) blading efficiency
c) nozzle efficiency
d) mechanical efficiency
Answer: b
Explanation: Blading Efficiency is the ratio of work done on the blades to the energy supplied to the blades of a turbine.
2. A nozzle is said to be a convergent nozzle when?
a) the cross-section of the nozzle increases continuously from entrance to exit
b) the cross-section of the nozzle decreases continuously from entrance to exit
c) the cross-section of the nozzle first decreases from entrance to throat and then increases from its throat to exit
d) none of the mentioned
Answer: b
Explanation: In case of a convergent nozzle, the cross-section of the nozzle decreases continuously from entrance to exit.
3. Multi-stage steam turbines are of the ___________
a) reaction type
b) velocity compounded type
c) pressure compounded type
d) all of the mentioned
Answer: d
Explanation: There are various types of multi-stage steam turbines which are, reaction; velocity compounded; & pressure compounded, respectively.
4. The impulse reaction turbine has its driving force ___________
a) partly as an impulsive force and partly as a reaction force
b) as an impulsive force
c) as a reaction force
d) none of the mentioned
Answer: a
Explanation: The impulse reaction turbine has its driving force partly as an impulsive force & partly as a reaction force as the components add to the resultant.
5. In a nozzle, whole frictional loss is assumed to occur between ___________
a) inlet and throat
b) throat and exit
c) inlet and outlet
d) none of the mentioned
Answer: b
Explanation: In a nozzle, whole frictional loss is assumed to occur between the throat & exit of the nozzle.
6. The ratio of total useful heat drop to the total isentropic heat drop is called?
a) Rankine efficiency
b) Stage efficiency
c) Internal efficiency
d) None of the mentioned
Answer: c
Explanation: The ratio of total useful heat drop to the total isentropic heat drop is called internal efficiency.
7. What is the action of steam in a steam turbine?
a) neither static nor dynamic
b) dynamic
c) static
d) both dynamic & static
Answer: b
Explanation: Steam action in a steam turbine is Dynamic.
8. The critical pressure gives the velocity of steam at the throat ___________
a) equal to the velocity of sound
b) more than velocity of sound
c) less than the velocity of light
d) none of the mentioned
Answer: a
Explanation: The critical pressure gives the velocity of steam at the throat which is equal to the velocity of sound.
9. The isentropic enthalpy drop in moving blade is two-third of the isentropic enthalpy drop in fixed blades of a turbine. The degree of reaction will be ___________
a) 0.67
b) 0.4
c) 0.5
d) 0.56
Answer: a
Explanation: The required degree of reaction will be 0.67.
10. The flow through a nozzle is regarded as ___________
a) isothermal flow
b) isobaric flow
c) isochoric flow
d) isentropic flow
Answer: d
Explanation: The flow through a nozzle is regarded as isentropic flow.
Turbine Efficiency and Flow Through Nozzles – I
1. The steam leaves the nozzle at a ____________
a) low pressure and a high velocity
b) high pressure and a high velocity
c) high pressure and a low velocity
d) low pressure and a low velocity
Answer: a
Explanation: The steam leaves the nozzle at low pressure & a high velocity as the action of steam is best suited for turbine operations under these conditions.
2. When the back pressure of a nozzle is below the designed value of pressure at exit of nozzle, the nozzle is said to be ____________
a) overdamping
b) underdamping
c) chocked
d) none of the mentioned
Answer: b
Explanation: When the back pressure of a nozzle is below the designed value of pressure at exit of nozzle, the nozzle is said to be underdamping.
3. De-Laval turbine is a ____________
a) multi rotor impulse turbine
b) impulse reaction turbine
c) single rotor impulse turbine
d) none of the mentioned
Answer: c
Explanation: A De-Laval turbine is a single rotor impulse turbine.
4. The supersaturated flow of steam through a nozzle as compared to a stable flow, the available heat drop ____________
a) increases
b) decreases
c) is unpredictable
d) remains same
Answer: b
Explanation: The supersaturated flow of steam through a nozzle as compared to a stable flow, the available heat drop decreases.
5. A turbine is said to have an axial discharge when the steam leaves the blade tip at __________ to the direction of the blade motion.
a) 90°
b) 60°
c) 270°
d) 180°
Answer: b
Explanation: A turbine is said to have an axial discharge when the steam leaves the blade tip at 60°
to the direction of the blade motion.
6. The Parsons’ reaction turbine has ____________
a) only moving blades
b) only fixed blades
c) fixed and moving blades of different shape
d) identical fixed and moving blade
Answer: d
Explanation: The Parsons’ reaction turbine has identical fixed & moving blades.
7. What is the critical pressure ratio for initially wet steam?
a) 0.582
b) 0.546
c) 0.577
d) 0.601
Answer: a
Explanation: The critical pressure ratio for initially wet steam is 0.582.
8. The ratio of the useful heat drop to the isentropic heat drop is called ____________
a) condenser efficiency
b) nozzle efficiency
c) vacuum efficiency
d) boiler efficiency
Answer: b
Explanation: The ratio of the useful heat drop to the isentropic heat drop is called nozzle efficiency.
9. Rateau turbine is ____________
a) pressure-velocity compounded turbine
b) simple reaction turbine
c) velocity compounded turbine
d) pressure compounded turbine
Answer: d
Explanation: A Rateau turbine is a pressure compounded turbine.
10. When the cross-section of a nozzle increases continuously from entrance to exit, it is called a ____________
a) convergent-divergent nozzle
b) divergent nozzle
c) convergent nozzle
d) none of the mentioned
Answer: b
Explanation: When the cross-section of a nozzle increases continuously from entrance to exit, it is called a divergent nozzle.
Turbine Efficiency and Flow Through Nozzles – II
1. The value of the reheat factor varies from ____________
a) 1.08 to 1.10
b) 1.2 to 1.6
c) 1.6 to 2
d) 1.02 to 1.06
Answer: d
Explanation: The value of the reheat factor varies from 1.02 to 1.06.
2. The difference in supersaturated temperature and saturation temperature at that pressure is called ____________
a) degree of super saturation
b) degree of superheat
c) degree of undercooling
d) none of the mentioned
Answer: c
Explanation: The difference of supersaturated temperature and saturation temperature at that pressure is called degree of undercooling.
3. Parson’s turbine is a ____________
a) simple impulse turbine
b) impulse-reaction turbine
c) simple reaction turbine
d) none of the mentioned
Answer: c
Explanation: Parson’s turbine is a simple reaction turbine.
4. In reaction turbines, the axial thrust is due to ____________
a) pressure drop across the rotor
b) change in axial velocity
c) both pressure drop across the rotor and change in axial velocity
d) none of the mentioned
Answer: c
Explanation: In reaction turbines, the axial thrust is due to the pressure drop across the rotor & change in axial velocity.
5. The flow of steam is super-sonic ____________
a) in the convergent portion of the nozzle
b) at the entrance to the nozzle
c) at the throat of the nozzle
d) in the divergent portion of the nozzle
Answer: d
Explanation: The flow of steam is super-sonic in the divergent portion of the nozzle.
Basic Thermodynamic Cycle MCQs
6. The variation of steam pressure in the nozzle depends upon ____________
a) dryness fraction of steam
b) specific volume of steam
c) velocity of steam
d) all of the mentioned
Answer: d
Explanation: The variation of steam pressure in the nozzle depends upon dryness fraction of steam, specifically volume of steam & velocity of steam.
7. A binary vapour plant consists of ____________
a) mercury boiler
b) steam turbine
c) steam condenser
d) all of the mentioned
Answer: d
Explanation: A binary vapour plant consists of mercury boiler, steam turbine, steam condenser, etc.
8. The steam enters the nozzle at a ____________
a) low pressure and a low velocity
b) high pressure and a low velocity
c) low pressure and a high velocity
d) high pressure and a high velocity
Answer: d
Explanation: The steam enters the nozzle at a high pressure & a high velocity to force the maximum volume into the nozzle.
9. In a reaction turbine, when steam flows through the fixed blades ____________
a) pressure decreases while velocity increases
b) pressure increases while velocity decreases
c) pressure and velocity both increases
d) pressure and velocity both decreases
Answer: a
Explanation: In a reaction turbine, when steam flows through the fixed blades, the pressure decreases while velocity increases.
10. The impulse turbine rotor efficiency will have a maximum value of 0.5 cos2 α, where α is the nozzle exit flow angle, if the ____________
a) blades are equiangular
b) blade velocity coefficient is unity
c) blade solidity is 0.65
d) blades are equiangular and frictionless
Answer: d
Explanation: The impulse turbine rotor efficiency will have a maximum value of 0.5 cos2 α, where α is the nozzle exit flow angle, if the blades are equiangular & frictionless.
11. Steam turbines are used for ____________
a) electric power generation
b) large marine propulsion
c) direct drive of fans, compressors, pumps
d) all of the mentioned
Answer: d
Explanation: Steam turbines are used for various applications which include, electric power generation, large marine propulsion, direct drive of fans, compressors, pumps, etc.
12. Curtis turbine is a ____________
a) pressure compounded turbine
b) velocity compounded turbine
c) simple reaction turbine
d) pressure-velocity compounded turbine
Answer: d
Explanation: A type of the pressure-velocity compounded turbine is a Curtis Turbine.
13. Which of the following statement is correct?
a) The expansion of steam in a nozzle follows Rankine cycle
b) The friction in the nozzle increases the dryness fraction of steam
c) The pressure of steam at throat is called critical pressure
d) All of the mentioned
Answer: d
Explanation: All the mentioned statements are correct.
14. Parson’s reaction turbine is a __________ reaction turbine.
a) 40%
b) 50%
c) 60%
d) 70%
Answer: b
Explanation: Parson’s reaction turbine is a 50% reaction turbine.
15. The diagram efficiency is the ratio of ____________
a) work done on the blades to the energy supplied to the blades
b) energy supplied to the blades per kg of steam to the total energy supplied per stage per kg of steam
c) work done on the blades per kg of steam to the total energy supplied per stage per kg of steam
d) none of the mentioned
Answer: a
Explanation: The diagram efficiency is the ratio of work done on the blades to the energy supplied to the blades.
Turbine and Nozzles Types
1. What is the purpose of governing in steam turbines?
a) reheat the steam and improve its quality
b) maintain the speed of the turbine
c) reduce the effective heat drop
d) completely balance against end thrust
Answer: b
Explanation: The purpose of governing in steam turbines is to maintain the speed of the turbine.
2. 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?
a) nozzle efficiency
b) stage efficiency
c) mechanical efficiency
d) blading efficiency
Answer: b
Explanation: 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 Stage Efficiency.
3. A nozzle is said to be a divergent nozzle ____________
a) when the cross-section of the nozzle increases continuously from entrance to exit
b) when the cross-section of the nozzle decreases continuously from entrance to exit
c) when the cross-section of the nozzle first decreases from entrance to throat and then increases from its throat to exit
d) none of the mentioned
Answer: a
Explanation: A nozzle is said to be a divergent nozzle when the cross-section of the nozzle increases continuously from entrance to exit.
4. The ratio of the isentropic heat drop to the heat supplied is called ____________
a) stage efficiency
b) reheat factor
c) internal efficiency
d) rankine efficiency
Answer: d
Explanation: The ratio of the isentropic heat drop to the heat supplied is called Rankine efficiency.
5. The reheat factor depends upon ____________
a) exit pressure
b) turbine stage efficiency
c) initial pressure and superheat
d) all of the mentioned
Answer: d
Explanation: The factors on which the reheat factor depends are exit pressure, turbine stage efficiency, initial pressure & superheat.
6. What is the critical pressure ratio for initially dry saturated steam?
a) 0.546
b) 0.577
c) 0.586
d) 0.578
Answer: b
Explanation: The critical pressure ratio for initially dry saturated steam is 0.577.
7. In order to reduce the rotor speed of an impulse turbine, the method employed is ____________
a) pressure compounding
b) velocity compounding
c) pressure-velocity compounding
d) all of the mentioned
Answer: d
Explanation: In order to reduce the rotor speed of an impulse turbine, the methods employed are
Pressure compounding, Velocity compounding, Pressure-Velocity compounding, etc.
8. Which of the following statement is wrong?
a) The flowing the convergent portion of the nozzle is sub-sonic
b) The critical pressure gives the velocity of steam at the throat equal to the velocity of sound
c) The flow in the divergent portion of the nozzle is super-sonic
d) To increase the velocity of steam above sonic velocity (super-sonic) by expanding steam below the critical pressure, the divergent portion for the nozzle is not necessary
Answer: d
Explanation: In order to increase the velocity of steam above sonic velocity by expanding steam below the critical pressure, the divergent portion for the nozzle is necessary.
9. In an impulse turbine, steam expands ____________
a) wholly in nozzle
b) partly in the nozzle and partly in blades
c) wholly in blades
d) none of the mentioned
Answer: a
Explanation: In an impulse turbine, steam expands wholly in nozzle.
10. A steam nozzle converts ____________
a) heat energy of steam into potential energy
b) potential energy into heat energy of steam
c) heat energy of steam into kinetic energy
d) kinetic energy into heat energy of steam
Answer: c
Explanation: A steam nozzle converts heat energy of steam into kinetic energy.
11. 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 the mentioned
Answer: c
Explanation: 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 Bleeding.
12. If the critical pressure ratio for steam is 0.546, then the steam is initially ____________
a) wet
b) dry saturated
c) superheated
d) none of the mentioned
Answer: c
Explanation: Generally, when the critical pressure ratio for steam is 0.546, then the steam is said to be superheated.
13. A steam turbine, in which a part of the steam after partial expansion, is used for process heating and the remaining steam is further expanded for power generation, is known as?
a) pass out turbine
b) impulse turbine
c) low pressure turbine
d) high pressure turbine
Answer: a
Explanation: A steam turbine, in which a part of the steam after partial expansion, is used for process heating and the remaining steam is further expanded for power generation, is known as Pass out Turbine.
14. A stage, in reaction turbine, is represented by ____________
a) each row of blades
b) number of entries of steam
c) number of exits of steam
d) none of the mentioned
Answer: a
Explanation: Each row of blades represents each stage in a reaction turbine.
15. Which of the following statement is correct?
a) The pressure of steam, in reaction turbines, is increased in fixed blades as well as in moving blades
b) The efficiency of steam turbine is greater than the steam engines
c) A flywheel is a must for steam turbine
d) The turbine blades do not change the direction of steam issuing from the nozzle
Answer: b
Explanation: The efficiency of steam turbines is greater than that of a steam engine.
Turbine Blading – I
1. In turbines, the fluid undergoes a continuous steady flow process and the speed of flow is ____________
a) very high
b) high
c) low
d) very low
Answer: a
Explanation: In turbines, the fluid undergoes a continuous steady flow process and the speed of flow is very high.
2. Steam turbines may be classified according to ____________
a) number of stages
b) direction of steam flow
c) mode of steam action
d) all of the mentioned
Answer: d
Explanation: The steam turbines are classed under various types based on number of stages, direction of steam flow, mode of steam action, etc.
3. A steam nozzle converts ____________
a) heat energy of steam into kinetic energy
b) kinetic energy of steam into heat energy
c) potential energy into heat energy
d) none of the mentioned
Answer: a
Explanation: A steam nozzle converts heat energy of steam into kinetic energy.
4. In a velocity compounded impulse turbine, when steam flows through the second row of moving blades ____________
a) velocity decreases
b) velocity increases
c) pressure decreases
d) pressure increases
Answer: a
Explanation: In a velocity compounded impulse turbine, when steam flows through the second row of moving blades, the velocity decreases.
5. In a reaction turbine when the degree of reaction is zero, then there is ____________
a) no heat drop in moving blades
b) maximum heat drop in fixed blades
c) no heat drop in fixed blades
d) maximum heat drop in moving blades
Answer: a
Explanation: In a reaction turbine when the degree of reaction is zero, then there isn’t any heat drop in moving blades.
6. 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 the mentioned
Answer: c
Explanation: 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 Bleeding.
7. Turbo alternators run at speeds ____________
a) constant speed of 3000 rpm
b) constant speed of 1000 rpm
c) variable speed of 1000 rpm
d) none of the mentioned
Answer: c
Explanation: The turbo alternators run at speeds varying in 1000 rpm.
8. In an impulse reaction turbine, the pressure drops gradually and continuously over ____________
a) moving blades
b) fixed blades
c) both moving & fixed blades
d) none of the mentioned
Answer: c
Explanation: The pressure drops gradually & continuously over both moving & fixed blades in an impulse turbine.
9. A steam turbine with no nozzle is?
a) Reaction Turbine
b) Impulse Turbine
c) Reaction & Impulse Turbines
d) None of the mentioned
Answer: a
Explanation: Reaction turbine is basically a steam turbine without any nozzle.
10. The pipes carrying steam are made up of?
a) Steel
b) Copper
c) Aluminium
d) Iron
Answer: a
Explanation: The pipes carrying steam in a steam turbine are made up of Steel.
Turbine Blading – II
1. Governing principle(s) of steam turbine is?
a) Nozzle control governing
b) Throttle governing
c) Bypass governing
d) All of the mentioned
Answer: d
Explanation: The various principles of Steam turbine governance are Nozzle control governing, bypass governing, throttle governing, etc.
2. Air-Preheater in a steam power plant _____________
a) Recovers the heat from the flue gases leaving the economiser
b) Improves combustion rate
c) Raises the temperature of the furnace gases
d) All of the mentioned
Answer: d
Explanation: Air- preheater in a steam power plant recovers the heat from the flue gases leaving the economiser, improves combustion rate, raises temperature of the furnace gases, etc.
3. What is the definition of the draught system?
a) A device used to pull in air
b) The difference between absolute gas pressure at any point in a gas flow and the ambient atmospheric pressure
c) The sum of the absolute gas pressure at any point in a gas flow and the ambient atmospheric pressure
d) A device used to pull out air
Answer: d
Explanation: The difference between absolute gas pressure at any point in a gas flow and the ambient atmospheric pressure is called Draught.
4. A condenser condenses the steam coming out from?
a) Boiler
b) Turbine
c) Economiser
d) Super heater
Answer: b
Explanation: The condensing action of a condenser begins when the steam comes out from the Turbine.
5. Water used in the steam plant is used for cooling in _______________
a) Condenser
b) Turbine only
c) Boiler tube
d) Boiler tubes and turbines
Answer: a
Explanation: The only condensing process in a steam power plant occurs in the condenser so the water used in the steam plant is used for cooling in Condenser.
6. What is use of the air pumps in the condenser?
a) Remove water
b) Air leaking in the condenser and to maintain the vacuum
c) Maintain atmospheric pressure and the condenser
d) Remove water & Air leaking in the condenser and to maintain the vacuum
Answer: b
Explanation: Air pumps used in the condenser are used to maintain the vacuum by letting air outside.
7. Spray ponds are used to cool the warm water coming from the condenser in ________
a) Large power plants
b) Small power plants
c) Medium power plants
d) Both medium and large power plants
Answer: b
Explanation: Spray ponds are used to cool the warm water coming from the condenser in small power plants.
8. Evaporative type of condenser has ________
a) Water in pipes surrounded by steam outside
b) Steam and cooling water mixed to give the condensate
c) Steam in pipes surrounded by water
d) None of the mentioned
Answer: c
Explanation: Steam in pipes surrounded by water is the evaporative type condenser.
9. Due to friction between the fluid & walls of the nozzle, the expansion process is?
a) reversible
b) irreversible
c) reversible adiabatic
d) irreversible adiabatic
Answer: d
Explanation: The friction between the walls of fluid & walls of the nozzle is irreversible & the entire process remains adiabatic.
10. The ratio of actual mass flow through the nozzle to the mass flow if the flow were isentropic is?
a) Coefficient of viscosity
b) Coefficient of velocity
c) Coefficient of discharge
d) None of the mentioned
Answer: c
Explanation: Coefficient of discharge is defined as the ratio of actual mass flow through the nozzle to the mass flow if the flow were isentropic.
Electricity Generation – I
1. Convergent part of the nozzle is usually sharp while the divergent one is?
a) slopy
b) gradual
c) slopy & gradual
d) none of the mentioned
Answer: b
Explanation: The divergent part of the nozzle is gradual in comparison to the convergent part.
2. What is another name of converging nozzle?
a) diverging nozzle
b) subsonic nozzle
c) supersonic nozzle
d) none of the mentioned
Answer: b
Explanation: Another name of converging nozzle is Subsonic Nozzle.
3. Based on the type of applications, the nozzles are divided into?
a) 3 types
b) 4 types
c) 2 types
d) 5 types
Answer: c
Explanation: There are 2 types of nozzles based on their applications, namely Reamed & Foil nozzles.
4. Which of the following is used in high pressure impulses stages of steam turbine?
a) Reamed Nozzles
b) Foil Nozzles
c) Reamed & Foil Nozzles
d) None of the mentioned
Answer: a
Explanation: Reamed nozzle is used in high pressure impulses stages of steam turbine.
5. Angle of divergence in reamed nozzles is?
a) 10 deg
b) 12 deg
c) 14 deg
d) 16 deg
Answer: b
Explanation: The angle of divergence in reamed nozzles is approx. 12 degrees.
6. The nozzle formed by curved airfoil sections is called?
a) Curved nozzle
b) Airfoil Nozzle
c) Foil nozzle
d) Reamed nozzle
Answer: c
Explanation: Foil nozzle is the nozzle formed by curved air foil sections.
7. There are mainly _______ types of turbines.
a) 2
b) 3
c) 4
d) 5
Answer: a
Explanation: There are mainly two types of Turbines- Impulse & Reaction Turbine.
8. Moving blades are placed next to ___________
a) Fixed blades
b) Nozzle
c) Nozzle vanes
d) None of the mentioned
Answer: c
Explanation: Moving blades are positioned next to the nozzle vanes to allow sufficient flow.
9. The incoming steam inside the turbine goes into ___________
a) Steam vanes
b) Steam chest
c) Nozzle vanes
d) Moving blades
Answer: b
Explanation: The incoming steam is housed into the steam chest situated just below the steam inlet.
10. One row of nozzles followed by one row of blades is called?
a) a group of turbine
b) a step of turbine
c) a process of turbine
d) a stage of turbine
Answer: d
Explanation: One row of nozzles followed by one row of blades is called a stage of Turbine.
Electricity Generation – II
1. Single stage impulse turbines are also called as?
a) Laval Turbines
b) Lancashire Turbines
c) Cochran Turbines
d) La Del turbines
Answer: a
Explanation: Laval Turbines are single-stage impulse turbines.
2. There are basically ______ Ways of compounding steam turbines.
a) 2
b) 3
c) 4
d) 5
Answer: a
Explanation: There are basically 2 ways of compounding steam turbines namely, Rateau staging & Curtis staging.
3. Rateau staging is another name for?
a) Pressure compounding
b) Velocity compounding
c) Pressure & Velocity compounding
d) None of the mentioned
Answer: a
Explanation: Pressure compounding is also called as Rateau staging.
4. The another name for Velocity compounding is?
a) Rateau Staging
b) Curtis staging
c) Rateau & Curtis staging
d) None of the mentioned
Answer: b
Explanation: The another name for Velocity compounding is Curtis Staging.
5. The Guide vanes remain stationary in?
a) Curtis staging
b) Rateau staging
c) Rateau & Curtis staging
d) None of the mentioned
Answer: a
Explanation: The guide vanes remain stationary in velocity compounding to ensure better operating efficiency.
6. The pressure drop in reaction turbines occurs in?
a) fixed blades
b) movable blades
c) both in nozzles & fixed blades
d) nozzles
Answer: c
Explanation: The pressure drop in reaction turbines occurs in both, the nozzle & in fixed blades.
7. The loss in efficiency from one stage to another is called?
a) Lost efficiency
b) Carry below efficiency
c) Carry-over efficiency
d) None of the mentioned
Answer: c
Explanation: Carry-over efficiency is defined as the loss in efficiency from one stage to another.
8. For straight blades, the minimum blade height is __________ of the mean blade ring diameter.
a) 20%
b) 30%
c) 40%
d) 50%
Answer: a
Explanation: For straight blades, the minimum blade height is 20% of the mean blade ring diameter.
9. Number of parallel exhausts required for a given steam flow rate of x is?
a) x/63.5
b) x/36.5
c) x/68.5
d) x/56.5
Answer: a
Explanation: Number of parallel exhausts required for a given steam flow rate of x is, x/63.5.
10. External loses occur ___________ turbine casing.
a) inside
b) outside
c) inside & outside
d) none of the mentioned
Answer: b
Explanation: External loses are those which occur outside the turbine casing.