Refrigeration and Air Conditioning MCQ
Refrigeration and Air Conditioning MCQ covers key topics like refrigeration cycles, compressors, refrigerants, heat transfer, psychrometry, HVAC systems, and cooling load calculations. These objective questions help students prepare effectively for engineering exams and HVAC-related competitive tests.
Q1. The unit of refrigeration is?
A. Ton of refrigeration
B. Kelvin
C. Pascal
D. Watt
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Q2. 1 Ton of refrigeration equals?
A. 3.5 kW
B. 210 kJ/hr
C. 1000 kcal/hr
D. 12000 BTU/hr
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Q3. The most commonly used refrigerant in domestic refrigerators is?
A. R-22
B. R-134a
C. R-11
D. R-717
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Q4. COP of a refrigerator is?
A. Heat rejected / Work input
B. Work input / Heat absorbed
C. Heat absorbed / Work input
D. Work output / Heat input
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Q5. In refrigeration, the evaporator is used to?
A. Reject heat
B. Absorb heat
C. Compress gas
D. Store refrigerant
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Q6. The compressor in a refrigeration system increases?
A. Pressure and temperature
B. Volume and pressure
C. Temperature only
D. Pressure only
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Q7. The ideal refrigeration cycle is?
A. Diesel cycle
B. Carnot cycle
C. Reverse Carnot cycle
D. Rankine cycle
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Q9. Which refrigeration component rejects heat?
A. Condenser
B. Evaporator
C. Throttle valve
D. Accumulator
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Q10. Saturated liquid-vapor mixture is found in?
A. Condenser outlet
B. Evaporator inlet
C. Compressor outlet
D. Expansion valve outlet
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Q11. Which expansion device is used in domestic refrigerators?
A. Thermostatic valve
B. Capillary tube
C. Automatic valve
D. Float valve
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Q12. The refrigerant should have?
A. High boiling point
B. Low boiling point
C. High critical temperature
D. Low latent heat
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Q13. The purpose of superheating refrigerant is?
A. Increase pressure
B. Ensure no liquid enters compressor
C. Increase mass flow rate
D. Improve heat rejection
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Q14. Which of the following is an eco-friendly refrigerant?
A. R-134a
B. R-600a
C. R-22
D. CFC-12
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Q15. Which refrigerant is used in large industrial plants?
A. R-717 (Ammonia)
B. R-22
C. R-12
D. R-113
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Q16. The main function of a thermostat is to?
A. Increase COP
B. Control temperature
C. Compress refrigerant
D. Store refrigerant
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Q17. Humidity is measured using?
A. Thermometer
B. Hygrometer
C. Anemometer
D. Manometer
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Q18. The most efficient refrigeration cycle is?
A. Vapor absorption cycle
B. Vapor compression cycle
C. Reverse Carnot cycle
D. Gas refrigeration cycle
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Q19. In air conditioning, ACH stands for?
A. Air cooling hours
B. Air change per hour
C. Air current heat
D. Air conditioner horsepower
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Q20. The device used to control refrigerant flow is?
A. Compressor
B. Evaporator
C. Expansion valve
D. Receiver
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Q21. Psychrometry deals with?
A. Gas dynamics
B. Moist air properties
C. Refrigerant chemistry
D. Fluid pressure
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Q22. The comfort air temperature range is?
A. 10–15°C
B. 15–18°C
C. 22–26°C
D. 28–30°C
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Q23. Dehumidification means?
A. Adding moisture
B. Removing moisture
C. Heating air
D. Cooling air only
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Q24. Refrigerants with zero ODP are?
A. CFC
B. HCFC
C. HFC
D. Ammonia and hydrocarbons
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Q25. The purpose of a condenser fan is to?
A. Cool compressor
B. Increase refrigerant pressure
C. Improve heat rejection
D. Control humidity
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Q26. Which coefficient indicates cooling performance?
A. COP
B. EER
C. SHR
D. GWP
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Q27. The dryness fraction at expansion valve outlet is?
A. 1.0
B. 0.0
C. 0.2–0.4
D. 0.8–0.9
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Q28. The refrigerant should be?
A. Corrosive
B. Toxic
C. Non-corrosive and safe
D. Highly reactive
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Q29. Which cycle is used in air refrigeration systems?
A. Joule cycle
B. Reverse Brayton cycle
C. Diesel cycle
D. Otto cycle
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