Steam and Gas Turbines MCQ (Multiple Choice Questions)

Here are 1000 Steam and Gas Turbines MCQ (Chapterwise).

1. What is a steam turbine?
a) Machine that uses pressurised steam to extract mechanical energy
b) Machine that uses pressurised steam to extract thermal energy
c) Machine that uses pressurised steam to extract kinetic energy
d) Machine that uses pressurised steam to extract electrical energy
View Answer

Answer: b
Explanation: A steam turbine is a machine that employs pressurised steam to extract thermal energy and use it to perform mechanical work on a spinning output shaft.

2. What is a gas turbine?
a) A machine that uses a combustion engine to convert liquid fuels into mechanical energy
b) A machine that uses a diesel engine to convert liquid fuels into mechanical energy
c) A machine that uses a combustion engine to convert liquid fuels into mechanical energy
d) A machine that uses a combustion engine to convert liquid fuels into electrical energy
View Answer

Answer: a
Explanation: A gas turbine is a machine used in a power plant that uses a combustion engine to convert natural gas or other liquid fuels into mechanical energy.

3. Which of the following is a type of turbine classified based on the fuel that supplies the driving force?
a) Steam Turbine
b) Gas Turbine
c) Wind Turbine
d) All of the mentioned
View Answer

Answer: d
Explanation: While turbines can be classified as impulse or reaction based on how they work, there are four basic types of turbines based on the fluid that provides the driving force: steam, gas, water, or wind.

4. What is rotor steam turbine?
a) Spinning component with wheels
b) Spinning component with wheels and blades disconnected
c) Spinning component with wheels and blades connected
d) Spinning component with blades
View Answer

Answer: c
Explanation: The rotor of a steam turbine is the spinning component with wheels and blades connected. The component that collects energy from the steam is the blade.

5. Why casing is used in turbine?
a) Forms the outside wall of the main flow duct to remain concentric
b) Forms the inside wall of the main flow duct to remain concentric
c) Forms the outside wall of the main flow duct to not remain concentric
d) None of the mentioned
View Answer

Answer: a
Explanation: Casing in the Turbines forms the outside wall of the main flow duct to remain reasonably concentric, allowing leakage past the turbine rotor tips to be controlled.
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6. Which of the following can also be called as Non Condensing steam turbine?
a) Back pressure steam turbine
b) Impulse steam turbine
c) Extraction steam turbine
d) None of the mentioned
View Answer

Answer: a
Explanation: The other name for Non condensing turbines is back pressure turbines.

7. Steam turbine is classified on basis of __________
a) type of Steam flow
b) type of blades
c) exhausting condition
d) all of the mentioned
View Answer

Answer: d
Explanation: Steam turbines are classified by type of blades, exhausting condition, type of steam flow, division of steam flow, type of compounding.

8. In which of the following Cross compound steam turbines was once used?
a) marine ships
b) automobiles
c) generation of electricity
d) none of the mentioned
View Answer

Answer: a
Explanation: Cross compound turbines are once used in marine ships before two stroke diesel engines.

9. Pankaj watches a jet in the air with a long trail of exhaust gas at its rear. What type of engine do they run on?
a) Jet Propulsion Gas Turbine
b) Prop Jet
c) Steam turbine
d) Back Pressure Gas Turbine
View Answer

Answer: c
Explanation: Jet propulsion turbine provides high velocity and comfortable flight at very high altitudes.

10. _______ of electricity in United States is produced using steam turbine.
a) 88%
b) 56%
c) 78%
d) 35%
View Answer

Answer: a
Explanation: 88% of electricity in United States is produced using steam turbine. US is one among the few countries that depends mostly on the steam turbine power plants.

11. In order to generate energy in Sahara Desert where water is available in significantly low amount. Which of the following system can we employ in such a place?
a) Gas Turbine
b) Tidal Engine
c) Steam Turbine
d) Gas & Steam Engine
View Answer

Answer: a
Explanation: As gas turbine require very little or no water at all for their functioning.

12. Gas and Steam turbine combined power plant produces more electricity than traditional power plants by how much percent?
a) 56
b) 94
c) 50
d) The given statement is false
View Answer

Answer: c
Explanation: When steam and gas turbines are jointly used in power plants and the power produced by gas and steam turbines is used in producing electricity.

13. Due to the limits, upper efficiency of steam turbines is fixed to _________
a) 5-10%
b) 15-30%
c) 40-50%
d) 35-45%
View Answer

Answer: d
Explanation: In steam and gas turbine combined power plants, steam turbines water is used as working medium. High pressure and high temperatures are required for these high pressures which in turn requires high strengths so expensive alloys like nickel and cobalt are used. These limit the upper efficiency to 35-45%.

14. ________ takes place due to thermal stresses in the steam turbine cylinder.
a) Depends
b) Expansion
c) Compression
d) None of the mentioned
View Answer

Answer: b
Explanation: Expansion takes place due to thermal stresses in the steam turbine cylinder. As steam turbine cylinders are made of some metal, thermal expansion may take place.
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15. High power density is the advantage obtained from _______
a) steam Turbines
b) cryogenic Gas turbines
c) solar Gas turbines
d) none of the mentioned
View Answer

Answer: c
Explanation: Gas turbines have higher power density than steam turbines and in the case of cryogenic gas turbines those could not be operated on solar power.

16. Gas turbine is also called as which of the following?
a) Steam turbine
b) Combustion turbine
c) Velocity turbine
d) None of the mentioned
View Answer

Answer: b
Explanation: In gas turbines fuel is combusted in combustor and hence it is also called as combustion turbines.

17. Superficial steam turbines releases _______ CO2.
a) low
b) does not release
c) high
d) none of the mentioned
View Answer

Answer: b
Explanation: Superficial steam turbine releases less pollutants. Because there will be less wastage of heat and hence pollutants are controlled.

18. Steam turbines work on __________
a) Dual cycle
b) Rankine cycle
c) Otto cycle
d) None of the mentioned
View Answer

Answer: b
Explanation: Otto cycle petrol is used as fuel, Rankine cycle is the process followed in steam turbines.

19. What is the use of reheat cycle in steam turbines?
a) To increase steam pressure
b) To remove the moisture from the steam
c) To increase the steam temperature
d) None of the mentioned
View Answer

Answer: b
Explanation: Reheat cycle is worked with rankine cycle to remove the moisture from the steam.
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20. Thickness of the cylinder wall must be ________ in steam turbines.
a) decreasing
b) constant
c) increased
d) none of the mentioned
View Answer

Answer: b
Explanation: Thickness of the cylinder wall must be maintained constant in steam turbines because if the thickness is uneven there will be uneven thermal stresses developed.

21. If Carnot cycle has maximum possible thermal efficiency, then why don’t the steam turbine power plants run on Carnot cycle?
a) Because boiler can’t be maintained at constant pressure in Carnot cycle
b) Since work consumed by compressor is approximately equal to work produced by turbine
c) As mean temperature of heat addition is quite low in case of Carnot cycle
d) Because the process of heat addition is at constant temperature
View Answer

Answer: b
Explanation: As compressor and turbine both work on wet steam, therefore they don’t have significant difference in their work.

22. Gas turbines work on which of the following cycle?
a) Diesel cycle
b) Brayton cycle
c) Rankine cycle
d) None of the mentioned
View Answer

Answer: b
Explanation: Rankine cycle is used in steam turbines. Brayton cycle is followed in gas turbines.

23. What does aerodynamic efficiency mean?
a) Amount of energy contained in steam
b) Energy that can be extracted from a given volume of steam at given temperature and pressure
c) Amount of steam turbine blade can allow to flow inside
d) None of the mentioned
View Answer

Answer: b
Explanation: Aerodynamic efficiency means energy that can be extracted from given volume of steam at given pressure and temperature.

24. Steam turbine governing can be defined as __________
a) controlling the flow rate of steam
b) increasing the steam speed
c) adjusting the governors for particular speeds
d) none of the mentioned
View Answer

Answer: a
Explanation: Governors are used to control the fuel needed to the load and they are no way related to the steam turbine governing. Steam turbine governing is controlling the flow rate of steam.

25. In steam turbines carry over losses are due to _____________
a) increase in temperature
b) formation of eddies in annular spaces
c) decrease in pressure
d) none of the mentioned
View Answer

Answer: b
Explanation: Carry over losses are due to formation of eddies in steam turbines.

26. Pressure ratios below 20 are used in _____________ engines.
a) aero derivative engines
b) heavy frame engines
c) steam turbine
d) none of the mentioned
View Answer

Answer: b
Explanation: Lower pressure ratios are maintained in heavy frame engines.

27. Why Hydrogen rings are used in gas turbine?
a) to control Oxygen consumption
b) to control Hydrogen consumption
c) to control Fuel consumption
d) None of the mentioned
View Answer

Answer: b
Explanation: Hydrogen rings are used to control hydrogen consumption in gas turbine. Hydrogen is used as coolant in gas turbine, Excessive usage of coolant leads to low efficiency.

28. Which of the following can be used as fuels in gas turbines?
a) petroleum
b) Diesel
c) Natural gases
d) All of the mentioned
View Answer

Answer: d
Explanation: Natural gases,petrol,diesel etc can be used as fuels in gas turbines. Gas turbines requires liquids with high specific heat as fuels.

29. Why is steam turbine governing used?
a) To increase the steam speed
b) To decrease the steam speed
c) To maintain steam speed constant
d) None of the mentioned
View Answer

Answer: c
Explanation: Flow rate if steam is controlled to maintain the constant speed.

30. In a steam turbine a set of ________ blades are connected to casing.
a) stationary & rotating
b) stationary
c) rotating
d) none of the mentioned
View Answer

Answer: c
Explanation: In a steam turbine a set of stationary blades are connected to casing.

31. Passages in steam turbines are _______
a) convergent & divergent
b) convergent
c) divergent
d) none of the mentioned
View Answer

Answer: b
Explanation: Passages in steam turbines are convergent so that steam expands.

32. Steam turbine performance is expressed in _______
a) heat & steam rate
b) heat rate
c) steam rate
d) none of the mentioned
View Answer

Answer: c
Explanation: Steam turbine performance is expressed in steam rate.

33. When initial pressure of the steam turbine is not upto the designed pressure then power produced will _________
a) Remains constant
b) Increase
c) Decrease
d) None of the mentioned
View Answer

Answer: c
Explanation: When initial pressure of the steam turbine is less than the designed pressure it power production is reduced.

34. Steam turbines used in nuclear reactors use __________
a) Specific heat
b) Superficial fluids
c) High pressure steam
d) None of the mentioned
View Answer

Answer: b
Explanation: Steam turbines used in nuclear reactors use superficial fluids. High pressure steam is also called as superficial fluid. Steam used in nuclear reactors need to have high kinetic energy where kinetic energy in superficial fluid is sufficient for nuclear reactor.

35. Superficial steam turbines can be operated at ________
a) low speeds
b) high speeds
c) medium speeds
d) none of the mentioned
View Answer

Answer: b
Explanation: Superficial steam turbines can be operated at high speeds. Because it produces high heat energy which can be converted into rotational energy.


Chapterwise Multiple Choice Questions on Steam and Gas Turbines

Steam and Gas Turbines MCQ - Multiple Choice Questions and Answers

Our 1000+ MCQs focus on all topics of the Steam and Gas Turbines subject, covering 100+ topics. This will help you to prepare for exams, contests, online tests, quizzes, viva-voce, interviews, and certifications. You can practice these MCQs chapter by chapter starting from the 1st chapter or you can jump to any chapter of your choice.
  1. Basics and Classification
  2. Turbine Thermodynamics and Efficiency
  3. Steam and Gas Turbines – Anatomy, Characteristics and Functioning
  4. Turbine Blade Profile
  5. Steam Turbine – Governers, Regulators and Performance
  6. Steam and Gas Turbines – Combustion and Regeneration
  7. Steam and Gas Turbines – Power Plant
  8. Gas Turbines – Anatomy and Applications
  9. Anatomy and Applications

1. Steam and Gas Turbines MCQ on Basics and Classification

The section contains Steam and Gas Turbines multiple choice questions and answers on types and nomenclature of steam turbines, flow passage and flow arrangement classification, types of engines and their components, application, cycle and fuel classification, basics and advantages of turbine and combined power plant.

  • Types
  • Flow Passages and Arrangement Classification
  • Types, Engine and Component – 1
  • Types, Engine and Component – 2
  • Application, Cycle and Fuel Classification – 1
  • Application, Cycle and Fuel Classification – 2
  • Combined Power Plant
  • Advantages
  • Introduction
  • 2. Steam and Gas Turbines Multiple Choice Questions on Turbine Thermodynamics and Efficiency

    The section contains Steam and Gas Turbines questions and answers on basics of thermodynamics, carnot, rankine and reheat cycles, temperature and pressure effect on cycle efficiency, heat and steam rate, sterling cycle, ericsson cycle, intercooling, reheating and regeneration.

  • Thermodynamics Basics
  • Carnot and Rankine Cycle – 1
  • Carnot and Rankine Cycle – 2
  • Temperature and Pressure Effect
  • Efficiencies
  • Heat and Steam rate – 1
  • Heat and Steam Rate – 2
  • Sterling and Ideal Ericsson Cycle
  • Ideal and Actual Intercooling
  • Intercooling,Reheating and Regeneration Effect
  • 3. Steam and Gas Turbines – Anatomy, Characteristics and Functioning MCQ

    The section contains Steam and Gas Turbines MCQs on closed cycle, nozzle design, shock wave, position angles, types of steam, turbine flow passage design, energy distribution, cascade principle, design calculations for impulse and multistaged turbine flow passages, blade, bending and disk stresses, shrouding and lacing wires and other metallurgical considerations.

  • Closed Cycles and Media
  • Nozzle Design
  • Critical Pressure Ratio
  • Nozzle Losses
  • Divergence Angles
  • Wet and Supersaturated Steam
  • Nozzle Discharge Coefficients
  • Turbine Flow Passage Design
  • Carry-Over Velocity Effect
  • Radial Equilibrium and Velocity Diagrams
  • Airfoil Principle and Limitations
  • Cascade Principle
  • Velocity Ratio Relationship
  • Turbine Rotor and Blade Stresses
  • Bending Stresses and Vibrations
  • Disk Stresses and Blade Fastening
  • Shrouding and Lacing Wires
  • Gas Turbine Blade Cooling
  • Casing & Metallurgical Considerations
  • 4. Steam and Gas Turbines Multiple Choice Questions on Turbine Blade Profile

    The section contains Steam and Gas Turbines multiple choice questions and answers on turbine, impulse and reaction blade profiles, blade entrance and exit angles, losses and geometry of impulse blade profiles and passages, gauging and pitch and free and forced vertex.

  • Turbine Blade Profile
  • Blade Entrance and Exit Angles
  • Impulse Blade Passage Loss
  • Reaction Blade Profiles
  • Blade Angle,Width and Height
  • Reaction Blade Passage Loss
  • Radial Equilibrium Flow
  • Free and Forced Vortex
  • 5. MCQ on Steam Turbine – Governers, Regulators and Performance

    The section contains Steam and Gas Turbines questions and answers on control, performance and supervisory instruments, direct speed and hydraulic speed responsive governors, speed and pressure regulators and their operation, effects of throttle governing, nozzle governing, temperature changes, compressibility effect, adiabatic efficiency, parson’s number and quality factor, surging and turbine performances.

  • Control and Performance
  • Control and Supervisory Instruments
  • Direct Speed Governors
  • Hydraulic Speed Governor
  • Pressure Regulators
  • Speed Regulation
  • Emergency Governors
  • Turbine Performance
  • Initial Pressure and Temperature Effect
  • Nozzle Governing Effect
  • Parsons Number and Quality Factor
  • Automatic Extraction Turbines
  • Mixed Pressure Turbine
  • AIEE-ASME Preffered Turbine
  • Centrifugal Compressor
  • Energy Transfer Relation
  • Adiabatic Efficiency
  • Compressibility Effect
  • The Diffuser and Prewhirl
  • Performance Characteristics
  • Pressure Coefficients
  • Surging
  • Centrifugal Compressors Design
  • 6. Multiple Choice Questions on Steam and Gas Turbines – Combustion and Regeneration

    The section contains Steam and Gas Turbines MCQs on combustion and its mechanics, thermochemistry, entropy, equilibrium, combustor, regenerator, its types, calculations and effectiveness, atomization, pressure losses and film coefficient.

  • Combustion and Thermochemistry
  • Entropy and Heat of Reaction
  • Flame Temperature and Dissociation
  • Combustion Mechanics
  • Physical Characteristics of Combustion
  • The Combustor
  • Fuel Injection and Combustion Chamber
  • The Regenerator
  • Regenerator Types
  • Film Coefficient and Regenerator Effectiveness
  • Regenerator Design Economic Aspect
  • 7. MCQ on Steam and Gas Turbines – Power Plant

    The section contains Steam and Gas Turbines multiple choice questions and answers on power plant, twin shaft plant, aircraft plant, dimension and dimensionless performance parameters for these plants, elementary gas dynamics and airfoil theory and properties of torque.

  • Power Plant
  • Dimensionless Performance Parameters
  • Twin Shaft Plant
  • Aircraft Plants Parameters
  • Torque Characteristics
  • Starting and Performance
  • Elementary Gas Dynamics
  • Elementary Airfoil Theory
  • 8. Multiple Choice Questions on Gas Turbines – Anatomy and Applications

    The section contains Steam and Gas Turbines questions and answers on usage of fuels, bearing systems, cryogenics and hot gas path in gas turbines, usage of gas turbines in jet engines and hybrid vehicles, turbine, inlet and compressor casing and exhaust frames and micro gas turbines.

  • Cryogenics in Gas Turbines
  • Gas Turbines in Jet Engines
  • Micro Gas Turbines
  • Fuel Systems in Gas Turbines
  • Bearing System in Gas Turbines
  • Combustion System in Gas Turbines
  • Turbine Casing and Exhaust Frames
  • Compressor Parts of Gas Turbines
  • Inlet and Compressor Casing
  • Gas Turbine Fuels
  • 9. Steam and Gas Turbines MCQ on Anatomy and Applications

    The section contains Steam and Gas Turbines MCQs on steam turbine working and fire resisting fluids in them, steam turbine cylinders and hydrogen seal rings in turbine generator.

  • Steam Turbine Working
  • Fire Resisting Fluids
  • Hydrogen Seal Rings
  • Steam Turbine Cylinders
  • If you would like to learn "Steam and Gas Turbines" thoroughly, you should attempt to work on the complete set of 1000+ MCQs - multiple choice questions and answers mentioned above. It will immensely help anyone trying to crack an exam or an interview.

    Wish you the best in your endeavor to learn and master Steam and Gas Turbines!

    Steam and Gas Turbines Online Tests:

    Additional Recommendations:

    Steam and Gas Turbines Books:

    • “Gas Turbine Theory” by Cohn H Rogers
    • “Steam Turbines and their Cycles” by Salisbury J K
    • “Heat Engines – Steam, Gas, Steam Turbines and their Auxiliaries” by Allen Bursley
    • “Combined-Cycle Gas & Steam Turbine Power Plants” by Kehlhofer
    • “Gas-Turbine Regenerators” by David G Wilson

    You can buy these Steam and Gas Turbines books from “Amazon USA” OR “Amazon India”.

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