Discussion
Home ‣ Mechanical Engineering ‣ Heat Transfer, Refrigeration and Air Conditioning Comments
- Question
The lowest temperature during the cycle in a vapour compression system occurs after
Options- A. compression
- B. expansion
- C. condensation
- D. evaporation
- Correct Answer
- evaporation
- 1. The process of heat transfer from one particle of the body to another by the actual motion of the heated particles, is called
Options- A. conduction
- B. convection
- C. radiation Discuss
- 2. A steam pipe is to be lined with two layers of insulating materials of different thermal conductivities. For the minimum heat transfer,
Options- A. the better insulation must be put inside
- B. the better insulation must be put outside
- C. one could place either insulation on either side
- D. one should take into account the steam temperature before deciding as to which insulation is put where Discuss
- 3. The material of pipe lines for a system using freon as a refrigerant should be
Options- A. brass
- B. copper
- C. steel
- D. aluminium Discuss
- 4. The process of heat transfer from one particle of the fluid to another by the actual movement of the fluid particles due to difference of density caused by temperature of the particle is known as
Options- A. conduction
- B. free convection
- C. forced convection
- D. radiation Discuss
- 5. During sensible heating of air __________ decreases.
Options- A. wet bulb temperature
- B. relative humidity
- C. dry bulb temperature
- D. specific humidity Discuss
- 6. When the air is passed through an insulated chamber having sprays of water maintained at a temperature higher than the dew point temperature of entering air but lower than its dry bulb temperature, then the air is said to be
Options- A. cooled and humidified
- B. cooled and dehumidified
- C. heated and humidified
- D. heated and dehumidified Discuss
- 7. The refrigerant used in small-tonnage commercial machines (hermetically sealed units) is
Options- A. ammonia
- B. carbon dioxide
- C. sulphur dioxide
- D. R-12 Discuss
- 8. In a vapour absorption refrigeration system, the compressor of the vapour compression system is replaced by
Options- A. liquid pump
- B. generator
- C. absorber and generator
- D. absorber, generator and liquid pump Discuss
- 9. A refrigerant compressor is used to
Options- A. raise the pressure of the refrigerant
- B. raise the temperature of the refrigerant
- C. circulate the refrigerant through the refrigerating system
- D. all of the above Discuss
- 10. In aircraft, air refrigeration Cycle is used because of
Options- A. low weight per tonne of refrigeration
- B. high heat transfer rate
- C. low temperature at high altitudes
- D. higher coefficient of performance Discuss
Heat Transfer, Refrigeration and Air Conditioning problems
Search Results
Correct Answer: convection
Correct Answer: the better insulation must be put inside
Correct Answer: copper
Correct Answer: free convection
Correct Answer: relative humidity
Correct Answer: cooled and humidified
Correct Answer: sulphur dioxide
Correct Answer: absorber, generator and liquid pump
Correct Answer: all of the above
Correct Answer: low weight per tonne of refrigeration
Comments
There are no comments.More in Mechanical Engineering:
Programming
Copyright ©CuriousTab. All rights reserved.