Power Engineer Second 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 purpose of the boiler is to:
A. Convert mechanical energy into electrical energy
B. Convert water into high-pressure steam using heat energy
C. Condense exhaust steam into water
D. Increase the speed of the turbine shaft
Answer: B. Convert water into high-pressure steam using heat energy
The boiler is the component where heat from fuel combustion or another
heat source is transferred to water to produce steam at the required
pressure and temperature for turbine operation.
2. The main function of a steam turbine governor is to:
A. Control the condenser vacuum
B. Maintain the boiler water level
C. Regulate turbine speed by controlling steam flow
D. Increase steam temperature
Answer: C. Regulate turbine speed by controlling steam flow
,A turbine governor automatically adjusts steam admission to maintain
constant turbine speed despite changes in electrical load.
3. The efficiency of a boiler is defined as the ratio of:
A. Heat supplied by fuel to heat lost through gases
B. Heat utilized in steam generation to heat supplied by fuel
C. Steam pressure to fuel consumption
D. Steam temperature to boiler pressure
Answer: B. Heat utilized in steam generation to heat supplied by fuel
Boiler efficiency measures how effectively the boiler converts fuel energy
into useful steam energy.
4. The device used to remove dissolved gases from boiler feedwater is
called a:
A. Economizer
B. Superheater
C. Deaerator
D. Air preheater
Answer: C. Deaerator
A deaerator removes oxygen and carbon dioxide from feedwater to reduce
corrosion inside boilers and piping systems.
5. The purpose of a superheater in a boiler system is to:
A. Reduce steam pressure
B. Increase steam temperature above saturation temperature
,C. Remove impurities from water
D. Cool combustion gases
Answer: B. Increase steam temperature above saturation temperature
A superheater raises the temperature of saturated steam to improve
turbine efficiency and reduce moisture formation.
6. The primary function of a condenser in a steam power plant is to:
A. Increase steam pressure
B. Convert exhaust steam into water
C. Heat combustion air
D. Increase boiler temperature
Answer: B. Convert exhaust steam into water
The condenser changes low-pressure exhaust steam from the turbine back
into water for reuse as boiler feedwater.
7. Cavitation in a pump occurs when:
A. Pump speed is too low
B. Fluid pressure falls below vapor pressure causing vapor bubbles
C. Motor voltage increases
D. The pump casing becomes hot
Answer: B. Fluid pressure falls below vapor pressure causing vapor bubbles
Cavitation occurs when local pressure reduction causes liquid to vaporize,
producing damaging bubbles inside the pump.
, 8. The purpose of an economizer in a boiler is to:
A. Heat feedwater using waste heat from flue gases
B. Increase steam pressure directly
C. Remove ash from fuel
D. Cool the turbine exhaust
Answer: A. Heat feedwater using waste heat from flue gases
An economizer improves boiler efficiency by recovering heat from exhaust
gases to preheat incoming water.
9. The main function of a forced draft fan in a boiler is to:
A. Remove steam from the turbine
B. Supply combustion air to the furnace
C. Pump water into the condenser
D. Reduce fuel temperature
Answer: B. Supply combustion air to the furnace
Forced draft fans provide the required air supply for efficient fuel
combustion inside the boiler furnace.
10. A safety valve on a boiler is designed to:
A. Control fuel pressure
B. Prevent excessive steam pressure buildup
C. Increase steam flow
D. Reduce water temperature
Answer: B. Prevent excessive steam pressure buildup
Practice Questions And Correct Answers
(Verified Answers) Plus Rationale 2026
Q&A| Instant Download Pdf
1. In a steam power plant, the primary purpose of the boiler is to:
A. Convert mechanical energy into electrical energy
B. Convert water into high-pressure steam using heat energy
C. Condense exhaust steam into water
D. Increase the speed of the turbine shaft
Answer: B. Convert water into high-pressure steam using heat energy
The boiler is the component where heat from fuel combustion or another
heat source is transferred to water to produce steam at the required
pressure and temperature for turbine operation.
2. The main function of a steam turbine governor is to:
A. Control the condenser vacuum
B. Maintain the boiler water level
C. Regulate turbine speed by controlling steam flow
D. Increase steam temperature
Answer: C. Regulate turbine speed by controlling steam flow
,A turbine governor automatically adjusts steam admission to maintain
constant turbine speed despite changes in electrical load.
3. The efficiency of a boiler is defined as the ratio of:
A. Heat supplied by fuel to heat lost through gases
B. Heat utilized in steam generation to heat supplied by fuel
C. Steam pressure to fuel consumption
D. Steam temperature to boiler pressure
Answer: B. Heat utilized in steam generation to heat supplied by fuel
Boiler efficiency measures how effectively the boiler converts fuel energy
into useful steam energy.
4. The device used to remove dissolved gases from boiler feedwater is
called a:
A. Economizer
B. Superheater
C. Deaerator
D. Air preheater
Answer: C. Deaerator
A deaerator removes oxygen and carbon dioxide from feedwater to reduce
corrosion inside boilers and piping systems.
5. The purpose of a superheater in a boiler system is to:
A. Reduce steam pressure
B. Increase steam temperature above saturation temperature
,C. Remove impurities from water
D. Cool combustion gases
Answer: B. Increase steam temperature above saturation temperature
A superheater raises the temperature of saturated steam to improve
turbine efficiency and reduce moisture formation.
6. The primary function of a condenser in a steam power plant is to:
A. Increase steam pressure
B. Convert exhaust steam into water
C. Heat combustion air
D. Increase boiler temperature
Answer: B. Convert exhaust steam into water
The condenser changes low-pressure exhaust steam from the turbine back
into water for reuse as boiler feedwater.
7. Cavitation in a pump occurs when:
A. Pump speed is too low
B. Fluid pressure falls below vapor pressure causing vapor bubbles
C. Motor voltage increases
D. The pump casing becomes hot
Answer: B. Fluid pressure falls below vapor pressure causing vapor bubbles
Cavitation occurs when local pressure reduction causes liquid to vaporize,
producing damaging bubbles inside the pump.
, 8. The purpose of an economizer in a boiler is to:
A. Heat feedwater using waste heat from flue gases
B. Increase steam pressure directly
C. Remove ash from fuel
D. Cool the turbine exhaust
Answer: A. Heat feedwater using waste heat from flue gases
An economizer improves boiler efficiency by recovering heat from exhaust
gases to preheat incoming water.
9. The main function of a forced draft fan in a boiler is to:
A. Remove steam from the turbine
B. Supply combustion air to the furnace
C. Pump water into the condenser
D. Reduce fuel temperature
Answer: B. Supply combustion air to the furnace
Forced draft fans provide the required air supply for efficient fuel
combustion inside the boiler furnace.
10. A safety valve on a boiler is designed to:
A. Control fuel pressure
B. Prevent excessive steam pressure buildup
C. Increase steam flow
D. Reduce water temperature
Answer: B. Prevent excessive steam pressure buildup
