Transit Railcar Maintenance Technician – Pneumatic, Brake,
and Air Systems Exam | Questions and Answers with
Rationales | 2026/2027 Update
Questions 1–25: Pneumatic Fundamentals
1. What is the primary medium used in a pneumatic system?
A. Hydraulic oil
B. Compressed air
C. Coolant
D. Grease
Answer: B
Rationale: Pneumatic systems use compressed air to transmit and
control energy.
2. Pressure is commonly measured in:
A. Volts
B. Ohms
C. PSI or kPa
D. Amperes
Answer: C
Rationale: Pounds per square inch and kilopascals are common
pressure units.
3. Increasing the pressure in a pneumatic actuator generally increases
its available:
A. Electrical resistance
B. Force
C. Voltage
D. Temperature only
,Answer: B
Rationale: Actuator force is related to air pressure and piston area.
4. A pneumatic actuator converts compressed-air energy into:
A. Mechanical motion
B. Electrical resistance
C. Battery capacity
D. Hydraulic pressure
Answer: A
Rationale: Pneumatic actuators use air pressure to produce mechanical
movement.
5. The basic relationship for actuator force is approximately:
A. Force = pressure × area
B. Force = voltage × resistance
C. Force = current ÷ voltage
D. Force = pressure ÷ temperature
Answer: A
Rationale: For an ideal actuator, force is approximately pressure
multiplied by effective piston area.
6. If pressure remains constant and piston area increases, actuator
force generally:
A. Increases
B. Decreases
C. Becomes zero
D. Remains unrelated
Answer: A
Rationale: A larger piston area produces greater force at the same
pressure.
,7. What is the main purpose of a pneumatic reservoir?
A. Store compressed air
B. Generate electricity
C. Lubricate bearings
D. Measure voltage
Answer: A
Rationale: Reservoirs store compressed air for later use and help
stabilize system pressure.
8. Why is compressed air stored in a reservoir?
A. To provide an available supply during demand
B. To eliminate all pressure variation
C. To increase electrical resistance
D. To replace every valve
Answer: A
Rationale: Stored air provides reserve capacity when pneumatic
components require air.
9. Air pressure generally decreases when:
A. Air is consumed from a closed reservoir without replenishment
B. The reservoir is properly isolated
C. The compressor operates normally
D. The system is completely static
Answer: A
Rationale: Removing air from a reservoir reduces the amount of stored
compressed air and therefore pressure.
10. A pressure regulator is primarily used to:
A. Control downstream pressure
B. Measure wheel diameter
, C. Store electricity
D. Increase mechanical friction
Answer: A
Rationale: Regulators maintain a controlled pressure downstream.
11. A pressure relief valve is designed primarily to:
A. Protect against excessive pressure
B. Increase system pressure indefinitely
C. Lubricate cylinders
D. Measure current
Answer: A
Rationale: Relief devices protect components from potentially
dangerous overpressure.
12. A pneumatic filter is used to:
A. Remove contaminants from compressed air
B. Increase electrical voltage
C. Increase brake shoe friction
D. Store air permanently
Answer: A
Rationale: Filters help remove particles and other contaminants from
compressed air.
13. Water can accumulate in compressed-air systems because:
A. Moisture can condense as air cools
B. Air cannot contain moisture
C. Pressure creates water chemically
D. Valves manufacture water
and Air Systems Exam | Questions and Answers with
Rationales | 2026/2027 Update
Questions 1–25: Pneumatic Fundamentals
1. What is the primary medium used in a pneumatic system?
A. Hydraulic oil
B. Compressed air
C. Coolant
D. Grease
Answer: B
Rationale: Pneumatic systems use compressed air to transmit and
control energy.
2. Pressure is commonly measured in:
A. Volts
B. Ohms
C. PSI or kPa
D. Amperes
Answer: C
Rationale: Pounds per square inch and kilopascals are common
pressure units.
3. Increasing the pressure in a pneumatic actuator generally increases
its available:
A. Electrical resistance
B. Force
C. Voltage
D. Temperature only
,Answer: B
Rationale: Actuator force is related to air pressure and piston area.
4. A pneumatic actuator converts compressed-air energy into:
A. Mechanical motion
B. Electrical resistance
C. Battery capacity
D. Hydraulic pressure
Answer: A
Rationale: Pneumatic actuators use air pressure to produce mechanical
movement.
5. The basic relationship for actuator force is approximately:
A. Force = pressure × area
B. Force = voltage × resistance
C. Force = current ÷ voltage
D. Force = pressure ÷ temperature
Answer: A
Rationale: For an ideal actuator, force is approximately pressure
multiplied by effective piston area.
6. If pressure remains constant and piston area increases, actuator
force generally:
A. Increases
B. Decreases
C. Becomes zero
D. Remains unrelated
Answer: A
Rationale: A larger piston area produces greater force at the same
pressure.
,7. What is the main purpose of a pneumatic reservoir?
A. Store compressed air
B. Generate electricity
C. Lubricate bearings
D. Measure voltage
Answer: A
Rationale: Reservoirs store compressed air for later use and help
stabilize system pressure.
8. Why is compressed air stored in a reservoir?
A. To provide an available supply during demand
B. To eliminate all pressure variation
C. To increase electrical resistance
D. To replace every valve
Answer: A
Rationale: Stored air provides reserve capacity when pneumatic
components require air.
9. Air pressure generally decreases when:
A. Air is consumed from a closed reservoir without replenishment
B. The reservoir is properly isolated
C. The compressor operates normally
D. The system is completely static
Answer: A
Rationale: Removing air from a reservoir reduces the amount of stored
compressed air and therefore pressure.
10. A pressure regulator is primarily used to:
A. Control downstream pressure
B. Measure wheel diameter
, C. Store electricity
D. Increase mechanical friction
Answer: A
Rationale: Regulators maintain a controlled pressure downstream.
11. A pressure relief valve is designed primarily to:
A. Protect against excessive pressure
B. Increase system pressure indefinitely
C. Lubricate cylinders
D. Measure current
Answer: A
Rationale: Relief devices protect components from potentially
dangerous overpressure.
12. A pneumatic filter is used to:
A. Remove contaminants from compressed air
B. Increase electrical voltage
C. Increase brake shoe friction
D. Store air permanently
Answer: A
Rationale: Filters help remove particles and other contaminants from
compressed air.
13. Water can accumulate in compressed-air systems because:
A. Moisture can condense as air cools
B. Air cannot contain moisture
C. Pressure creates water chemically
D. Valves manufacture water
