Power Engineer First Class Exam
Practice Questions And Correct Answers
(Verified Answers) Plus Rationale 2026
Q&A| Instant Download Pdf
1. In a steam power plant, the primary function of a boiler is to convert
water into high-pressure steam by using heat energy from fuel
combustion. Which boiler component is responsible for increasing the
temperature of saturated steam beyond its saturation point?
A. Economizer
B. Superheater
C. Air preheater
D. Feedwater heater
Answer: B. Superheater
The superheater raises the temperature of saturated steam above its
saturation temperature, producing dry superheated steam that improves
turbine efficiency and reduces moisture formation during expansion.
2. A power engineer observes that the boiler water level is continuously
decreasing despite normal feedwater pump operation. Which condition is
most likely responsible?
A. Excessive steam demand or leakage
B. High condenser vacuum
,C. Low fuel pressure
D. Increased cooling water flow
Answer: A. Excessive steam demand or leakage
A falling boiler water level indicates that water is being converted to
steam or lost faster than it is being replaced, commonly due to high steam
demand or system leakage.
3. The main purpose of a steam turbine governor is to:
A. Increase boiler pressure
B. Control turbine speed by regulating steam flow
C. Remove moisture from steam
D. Increase condenser temperature
Answer: B. Control turbine speed by regulating steam flow
A turbine governor maintains constant rotational speed by adjusting
steam admission according to load changes, preventing overspeed and
maintaining stable operation.
4. In a Rankine cycle power plant, the condenser performs which essential
function?
A. Converts feedwater into steam
B. Increases turbine inlet pressure
C. Condenses exhaust steam and maintains turbine back pressure
D. Separates dissolved gases from fuel
Answer: C. Condenses exhaust steam and maintains turbine back pressure
The condenser converts turbine exhaust steam back into water and creates
a vacuum that improves turbine expansion efficiency.
,5. A boiler safety valve is designed primarily to:
A. Control combustion air
B. Prevent excessive steam pressure buildup
C. Increase steam temperature
D. Improve fuel atomization
Answer: B. Prevent excessive steam pressure buildup
Safety valves automatically release steam when pressure exceeds a
predetermined limit, protecting the boiler from rupture or catastrophic
failure.
6. The purpose of an economizer installed in a boiler system is to:
A. Heat combustion air using exhaust gases
B. Preheat feedwater using waste heat from flue gases
C. Remove ash from combustion gases
D. Reduce steam pressure
Answer: B. Preheat feedwater using waste heat from flue gases
An economizer improves boiler efficiency by recovering heat from exhaust
gases to warm incoming feedwater before it enters the boiler.
7. Which instrument is commonly used to measure steam pressure in a
boiler?
A. Thermocouple
B. Pressure gauge
C. Flow meter
D. Tachometer
, Answer: B. Pressure gauge
A pressure gauge measures the internal steam pressure of a boiler and
allows operators to monitor safe operating conditions.
8. The main purpose of a deaerator in a steam power plant is to:
A. Increase steam pressure
B. Remove dissolved oxygen and gases from feedwater
C. Reduce turbine speed
D. Increase fuel efficiency
Answer: B. Remove dissolved oxygen and gases from feedwater
A deaerator removes corrosive dissolved gases such as oxygen and carbon
dioxide, protecting boilers and feedwater systems from corrosion.
9. Boiler blowdown is carried out to:
A. Increase dissolved solids concentration
B. Remove accumulated impurities from boiler water
C. Increase steam temperature
D. Reduce combustion efficiency
Answer: B. Remove accumulated impurities from boiler water
Blowdown removes concentrated dissolved solids and contaminants from
boiler water to maintain water quality and prevent scaling.
10. In electrical power systems, the main purpose of a transformer is to:
Practice Questions And Correct Answers
(Verified Answers) Plus Rationale 2026
Q&A| Instant Download Pdf
1. In a steam power plant, the primary function of a boiler is to convert
water into high-pressure steam by using heat energy from fuel
combustion. Which boiler component is responsible for increasing the
temperature of saturated steam beyond its saturation point?
A. Economizer
B. Superheater
C. Air preheater
D. Feedwater heater
Answer: B. Superheater
The superheater raises the temperature of saturated steam above its
saturation temperature, producing dry superheated steam that improves
turbine efficiency and reduces moisture formation during expansion.
2. A power engineer observes that the boiler water level is continuously
decreasing despite normal feedwater pump operation. Which condition is
most likely responsible?
A. Excessive steam demand or leakage
B. High condenser vacuum
,C. Low fuel pressure
D. Increased cooling water flow
Answer: A. Excessive steam demand or leakage
A falling boiler water level indicates that water is being converted to
steam or lost faster than it is being replaced, commonly due to high steam
demand or system leakage.
3. The main purpose of a steam turbine governor is to:
A. Increase boiler pressure
B. Control turbine speed by regulating steam flow
C. Remove moisture from steam
D. Increase condenser temperature
Answer: B. Control turbine speed by regulating steam flow
A turbine governor maintains constant rotational speed by adjusting
steam admission according to load changes, preventing overspeed and
maintaining stable operation.
4. In a Rankine cycle power plant, the condenser performs which essential
function?
A. Converts feedwater into steam
B. Increases turbine inlet pressure
C. Condenses exhaust steam and maintains turbine back pressure
D. Separates dissolved gases from fuel
Answer: C. Condenses exhaust steam and maintains turbine back pressure
The condenser converts turbine exhaust steam back into water and creates
a vacuum that improves turbine expansion efficiency.
,5. A boiler safety valve is designed primarily to:
A. Control combustion air
B. Prevent excessive steam pressure buildup
C. Increase steam temperature
D. Improve fuel atomization
Answer: B. Prevent excessive steam pressure buildup
Safety valves automatically release steam when pressure exceeds a
predetermined limit, protecting the boiler from rupture or catastrophic
failure.
6. The purpose of an economizer installed in a boiler system is to:
A. Heat combustion air using exhaust gases
B. Preheat feedwater using waste heat from flue gases
C. Remove ash from combustion gases
D. Reduce steam pressure
Answer: B. Preheat feedwater using waste heat from flue gases
An economizer improves boiler efficiency by recovering heat from exhaust
gases to warm incoming feedwater before it enters the boiler.
7. Which instrument is commonly used to measure steam pressure in a
boiler?
A. Thermocouple
B. Pressure gauge
C. Flow meter
D. Tachometer
, Answer: B. Pressure gauge
A pressure gauge measures the internal steam pressure of a boiler and
allows operators to monitor safe operating conditions.
8. The main purpose of a deaerator in a steam power plant is to:
A. Increase steam pressure
B. Remove dissolved oxygen and gases from feedwater
C. Reduce turbine speed
D. Increase fuel efficiency
Answer: B. Remove dissolved oxygen and gases from feedwater
A deaerator removes corrosive dissolved gases such as oxygen and carbon
dioxide, protecting boilers and feedwater systems from corrosion.
9. Boiler blowdown is carried out to:
A. Increase dissolved solids concentration
B. Remove accumulated impurities from boiler water
C. Increase steam temperature
D. Reduce combustion efficiency
Answer: B. Remove accumulated impurities from boiler water
Blowdown removes concentrated dissolved solids and contaminants from
boiler water to maintain water quality and prevent scaling.
10. In electrical power systems, the main purpose of a transformer is to:
