250+ TOP MCQs on Pneumatic Systems and Answers

Mechatronics Multiple Choice Questions on “Pneumatic Systems”.

1. In which type of system does power transmission takes place through compressed air?
a) Fluid power system
b) Hydraulic system
c) Pneumatic system
d) Stepper motors
Answer: c
Clarification: Pneumatic system is a power transmission system in which, the transmission of power takes place through compressed air. The mechanical energy is given to compressor, that is, the shaft of the compressor is rotated by any means of the prime mover. The fluid Power system is a power transmission system in which, the transmission of power takes place by means of “oil under pressure” or “compressed air”. If “oil under pressure” is used in the system for power transmission then the system is called a hydraulic system.

2. The compressed air flows to the actuator through ____
a) pipes and valves
b) shafts
c) motors
d) flow control valve
Answer: a
Clarification: Compressor drives air from the atmosphere and the compressed air flow through actuator through pipes and valves. Actuator produces back the mechanical energy that can either be the linear motion of cylinder or rotary motion of the air motor shaft. The other sources mentioned in the options are not the sources for the flow of compressed air.

3. The compressed air is delivered to the pneumatic system through the air compressor.
a) True
b) False
Answer: a
Clarification: The air compressor draws the air from the atmosphere, compresses it and delivers the compressed air to the pneumatic system. Compressor drives air from the atmosphere and the compressed air flow through actuator through pipes and valves.

4. What is the function of the air dryer?
a) Removes dirt
b) Removes moisture
c) Controls the rate of flow
d) Controls the pressure
Answer: b
Clarification: The compressed air delivered by the compressor contains moisture from the atmosphere. This moisture is separated and removed by the air dryer. Only the dry compressed air is given to the pneumatic system.

5. Which part of the Pneumatic system stores the compressed air?
a) Air dryer
b) Air compressor
c) Air receiver tank
d) Air lubricator
Answer: c
Clarification: The air receiver tank stores the compressed air. Apart from storing the compressed air, it has several other functions also. It acts as cooler to cool the hot compressed air. It acts as moisture separator to separate and remove the water

6. Pneumatic systems are very fast in operation.
a) True
b) False
Answer: a
Clarification: Pneumatic systems are very fast in operation. This is because of the low viscosity of compressed air. These systems can run continuously for a longer period and in any pneumatic system, the continuous free expansion of compressed air causes chilling effect and dues the continuous long run would not heat the system components.

7. Which among the following is not the component of FRL unit?
a) Air filter
b) Air dryer
c) Air regulator
d) Air lubricator
Answer: b
Clarification: The FRL unit does not consist of the air filter. It contains Air dryer, Air regulator and Air lubricator. The air filter removes the dust particles from compressed air and allows clean dry compressed air to the system. Air regulator controls the pressure of the compressed air and Air lubricator adds lubricating oil to the compressed air.

8. What is the function of the flow control valve?
a) Controls the direction of flow of air
b) The moisture is separated and removed
c) It converts the mechanical energy to hydraulic energy
d) It controls the rate of flow of compressed air
Answer: d
Clarification: The flow control valve controls the rate of flow of compressed air, by which, speed of extension or retraction of the actuator is controlled. The direction control valve controls the direction of the flow of oil.

9. The direction control valve controls ____
a) direction of flow
b) rate of flow
c) moisture
d) force and motion
Answer: a
Clarification: It controls the direction of flow of compressed air, by which, speed of extension or retraction of the actuator is controlled. The flow control valve controls the rate of flow of compressed air. This moisture is separated and removed by the air dryer. Force and motion are controlled through the double acting cylinder.

10. Which among the following is an advantage of the Pneumatic system?
a) The requirement of a lubricator
b) Runs continuously
c) Use of silencers
d) Low viscosity
Answer: b
Clarification: Pneumatic systems can run continuously for a longer period. Harder it runs, cooler it works. In any pneumatic system, the continuous free expansion of compressed air causes chilling effect and dues the continuous long run would not heat the system components. The other options mentioned are the disadvantages or limitations of the Pneumatic systems.

11. Which among the following is a disadvantage of Pneumatic system?
a) The requirement of a lubricator
b) Runs continuously
c) Used better in mines
d) Produces a dust free surroundings
Answer: a
Clarification: A lubricator is required in a Pneumatic system to add lubricant oil to compressed air or to minimize friction which is considered as one of the disadvantage or limitation of the system. The other options mentioned are the advantages of the Pneumatic systems.

12. Which among the following are not the applications of Pneumatic system?
a) Aerospace
b) Packing systems
c) Mining
d) Agriculture types of equipment
Answer: b
Clarification: The Pneumatic systems are not used in Aerospace activities; Hydraulic systems are used. The other options are the applications of Pneumatic systems. Packing is the final operation done on the product of any industry. The Pneumatic hand tools are extensively employed in mines. They are also used in shears and Pneumatic systems.