Multiple-Choice Questions or Objective-Type Questions on Compressors [PDF Included]

Compressors are one of the important equipment about which you must have a clear concept if you are a Mechanical Engineering student. Here, I will show some Multiple-Choice Questions on Compressors.

Compressor is the heart of the processes where increment of pressure of gas is primary requirement of the process. Like pumps, compressors also can transport the gas through the pipes.

Different types of compressors are available for different applications. These are Receprocating compressor, Rotary compressor, Screw compressor, Scroll compressor, Centrifugal compressor, etc.

In the middle section, there will be a Quiz on Compressors. I suggest that you first study the overview of compressor and then appear for the Quiz.

To download this MCQ sheet, you will find a PDF downloadable button at the end of this article. Click on that button and download the PDF version of this sheet.

So now let’s start the objective-type questions or viva questions.

MCQ questions or Viva Questions on Compressors

• Compressor is used to __ the pressure of a fluid.

1. increase
2. decrese
3. can’t say

Ans: (1)

• Pressure of which of the following substances can you increase by Compressor?

1. liquid
2. gas
3. both
4. none of these

Ans: (2)

• Pressure of which of the following substances can you increase by Pump?

1. liquid
2. gas
3. both
4. none of these

Ans: (1)

• How will you measure the compressor capacity?

1. By volume of air sucked by the compressor
2. By clearance volume
3. By volume of air delivered by the compressor
4. None of these

Ans: (3)

• Which volume will you define as swept volume?

1. Volume of air delivered by a compressor
2. Volume of air sucked by a compressor during suction
3. Clearance volume
4. None of these

Ans: (2)

• How will you determine the swept volume (D= diameter of cylinder bore, R= D/2, L= length of piston stroke)?

1. (Π/3)R^2.L
2. 2(Π/3)R^2.L
3. (Π/4)D^2.L
4. 2(Π/4)D^2.L

Ans: (3)

• Mean effective pressure of a compressor is

1. Work done per cycle/ stroke volume
2. Total work done / stroke volume
3. Stroke volume / work done per cycle
4. Stroke volume / total work done

Ans: (1)

• Which compressor can supply more volume of air?

1. Single acting reciprocating compressor
2. Double acting reciprocating compressor
3. None of these

Ans: (2)

• Work done on the air in a single acting reciprocating compressor is minimum when

1. Compression is isentropic
2. Compression is polytropic
3. Compression is isothermal
4. None of these

Ans: (3)

• Work done on the air in a single acting reciprocating compressor is maximum when

1. Compression is isentropic
2. Compression is polytropic
3. Compression is isothermal
4. None of these

Ans: (1)

• Before starting of the compression stroke, the pressure of air is ____ atmospheric pressure.

1. less than
2. more than
3. equal to
4. can’t say

Ans: (1)

• What do you mean by a 5 m3 /min compressor?

1. It compresses 5 m³/min of standard air
2. It delivers 5 m³/min of compressed air
3. It delivers 5 m³/min of compressed air at delivery pressure
4. It compresses 5 m³/min in of free air

Ans: (4)

• The requirement of intercooling in multi-stage compressor is

1. Cooling the air at delivery
2. Cooling the air at compression
3. Reducing the work of compression
4. Ease the compression in two stages

Ans: (3)

• The maximum delivery pressure in reciprocating air compressor is approximately:

1. 10 bar
2. 100 bar
3. 1000 bar
4. 10000 bar

Ans: (3)

• The maximum delivery pressure in rotary air compressor is approximately:

1. 10 bar
2. 100 bar
3. 1000 bar
4. 10000 bar

Ans: (1)

• What is the maximum free air discharge in a reciprocating air compressor?

1. 3 m³/min
2. 30 m³/min
3. 300 m³/min
4. 3000 m³/min

Ans: (3)

• What is the maximum free air discharge in a rotary air compressor?

1. 3 m³/min
2. 30 m³/min
3. 300 m³/min
4. 3000 m³/min

Ans: (4)

• Which of the following are positive displacement compressors?

1. Roots blower compressor
2. Vane blower compressor
3. Centrifugal blower compressor
4. Both (1) and (2)

Ans: (4)

• Which of the following are not positive displacement compressors?

1. Roots blower compressor
2. Vane blower compressor
3. Centrifugal blower compressor
4. Both (1) and (2)

Ans: (3)

• The axial flow compressor is of positive displacement compressor. Is it correct?

1. Yes
2. No
3. Can’t say

Ans: (2)

• In general, the number of slots that contain vanes in a disk of a vane blower compressor is:

1. 2 to 4
2. 8 to 16
3. 16 to 20
4. 4 to 8

Ans: (4)

• For delivering large amount of free air at low pressure, which compressor will you use?

1. Reciprocating compressor
2. Rotary compressor
3. Both (1) and (2)
4. None of these

Ans: (2)

• Speed of which air compressor is low?

1. Reciprocating compressor
2. Rotary compressor
3. Both (1) and (2)
4. None of these

Ans: (1)

• In which type of compressor, balancing problem occurs?

1. Reciprocating compressor
2. Rotary compressor
3. Both (1) and (2)
4. None of these

Ans: (1)

• In which type of compressor, supply of air should be continuous?

1. Reciprocating compressor
2. Rotary compressor
3. Both (1) and (2)
4. None of these

Ans: (2)

• Which type of rotary compressor is in the gas turbines?

1. Vane blower compressor
2. Centrifugal compressor
3. Axial flow compressor
4. None of these

Ans: (3)

• In which of the following compressor, the flow of air through the compressor is perpendicular to its axis?

1. Turbo compressor
2. Axial flow compressor
3. Reciprocating compressor
4. Centrifugal compressor

Ans: (4)

• In which of the following compressor, the flow of air through the compressor is parallel to its axis?

1. Turbo compressor
2. Axial flow compressor
3. Reciprocating compressor
4. Centrifugal compressor

Ans: (2)

• Which of the following rotary compressor is suitable for multi-staging?

1. Axial flow compressor
2. Centrifugal compressor
3. Both (1) and (2)
4. Reciprocating air compressor

Ans: (1)

• Mechanical efficiency of an air compressor is:

1. Isothermal power / shaft power
2. Shaft power / indicated power
3. Indicated power / isothermal power
4. Indicated power / shaft power

Ans: (4)

Quiz on Compressors

Here is the Quiz on Compressors for you.

Conclusion

I hope that the Multiple-Choice Questions on Compressors will help you in your college/university examinations and different types of competitive examinations. If you have any queries on this topic, please let me know by writing in the comment box. If you feel there is any contradiction in any MCQ answers, let me know by commenting here. In this way help me to make improvement of myself. Good Luck!