Home / Mechanical Engineering / Heat Transfer,Refrigeration and Air Conditioning :: Section 8

Mechanical Engineering :: Heat Transfer,Refrigeration and Air Conditioning

  1. The heat transfer from a hot body to a cold body is directly proportional to the surface area and difference of temperatures between the two bodies. This statement is called

  2. A.
    First law of thermodynamics
    B.
    Newton's law of cooling
    C.
    Newton's law of heating
    D.
    Stefan's law

  3. The pressure at the inlet of a refrigerant compressor is called

  4. A.
    suction pressure
    B.
    discharge pressure
    C.
    critical pressure
    D.
    back pressure

  5. The process, generally used in summer air conditioning to cool and dehumidify the air, is called

  6. A.
    humidification
    B.
    dehumidification
    C.
    heating and humidification
    D.
    cooling and dehumidification

  7. The leakage in a refrigeration system using ammonia is detected by

  8. A.
    halide torch
    B.
    sulphur sticks
    C.
    soap and water
    D.
    all of these

  9. The lowest temperature during the cycle in a vapour compression system occurs after

  10. A.
    compression
    B.
    expansion
    C.
    condensation
    D.
    evaporation

  11. The temperature of air recorded by a thermometer, when it is not effected by the moisture present in the air, is called

  12. A.
    wet bulb temperature
    B.
    dry bulb temperature
    C.
    dew point temperature
    D.
    none of these

  13. A human body feels comfortable when the heat produced by the metabolism of human body is equal to the

  14. A.
    heat dissipated to the surroundings
    B.
    heat stored in the human body
    C.
    sum of (a) and (b)
    D.
    difference of (a) and (b)

  15. During sensible cooling,

  16. A.
    relative humidity remains constant
    B.
    wet bulb temperature increases
    C.
    specific humidity increases
    D.
    partial pressure of vapour remains constant

  17. The wave length of the radiation emitted depends only on the temperature and is independent of the material of the body.

  18. A.
    True
    B.
    False

  19. The process of heat transfer from one particle of the body to another by the actual motion of the heated particles, is called

  20. A.
    conduction
    B.
    convection
    C.
    radiation