Discussion
Home ‣ Mechanical Engineering ‣ Heat Transfer, Refrigeration and Air Conditioning Comments
- Question
A water cooled condenser operates at a __________ condensing temperature than an air-cooled condenser.
Options- A. higher
- B. lower
- Correct Answer
- lower
- 1. Defrosting of a refrigerator may be done by stopping the compressor for a short period.
Options- A. Correct
- B. Incorrect Discuss
- 2. The optimum effective temperature for human comfort is
Options- A. higher in winter than in summer
- B. lower in winter than in summer
- C. same in winter and summer
- D. not dependent on season Discuss
- 3. The sensible heat factor during cooling and dehumidification process is given by (where h1 = Enthalpy of air entering the cooling coil, h2 = Enthalpy of air leaving the cooling coil, and hA = Enthalpy of air at the end of dehumidification process)
Options- A.
- B.
- C.
- D.
Discuss
- 4. The formation of frost on cooling coils in a refrigerator
Options- A. increases heat transfer
- B. improves C.O.P. of the system
- C. increases power consumption
- D. reduces power consumption Discuss
- 5. The by-pass factor for a cooling coil
Options- A. increases with increase in velocity of air passing through it
- B. decreases with increase in velocity of air passing through it
- C. remains unchanged with increase in velocity of air passing through it
- D. may increase or decrease with increase in velocity of air passing through it depending upon the condition of air entering Discuss
- 6. For ammonia refrigerating systems, the tubes of a shell and tube condenser are made of
Options- A. copper
- B. aluminium
- C. steel
- D. brass Discuss
- 7. In a psychrometric process, the sensible heat added is 30 kJ/s and the latent heat added is 20 kJ/s. The sensible heat factor for the process will be
Options- A. 0.3
- B. 0.6
- C. 0.67
- D. 1.5 Discuss
- 8. The heat transfer by conduction through a thick sphere is same as through a thick cylinder.
Options- A. True
- B. False Discuss
- 9. As relative humidity decreases, the dew point temperature will be __________ wet bulb temperature.
Options- A. same as
- B. lower than
- C. higher man Discuss
- 10. Which of the following statement is wrong?
Options- A. The heat transfer in liquid and gases takes place according to convection.
- B. The amount of heat flow through a body is dependent upon the material of the body.
- C. The thermal conductivity of solid metals increases with rise in temperature,
- D. Logarithmic mean temperature difference is not equal to the arithmetic mean temperature difference. Discuss
Heat Transfer, Refrigeration and Air Conditioning problems
Search Results
Correct Answer: Correct
Correct Answer: lower in winter than in summer
Correct Answer:
Correct Answer: increases power consumption
Correct Answer: increases with increase in velocity of air passing through it
Correct Answer: steel
Correct Answer: 0.6
Correct Answer: False
Correct Answer: lower than
Correct Answer: The thermal conductivity of solid metals increases with rise in temperature,
Comments
There are no comments.More in Mechanical Engineering:
Programming
Copyright ©CuriousTab. All rights reserved.