Home / Mechanical Engineering / Thermodynamics :: section-8

Mechanical Engineering :: Thermodynamics

  1. Kelvin-Planck’s law deals with

  2. A.

     Conservation of work

    B.

     Conservation of heat

    C.

     Conversion of work into heat

    D.

     Conversion of heat into work

    View Answer

    Workspace

    Discuss Discuss in Forum


  3. The thermal efficiency of an ideal gas turbine plant is given by (where r = Pressure ratio)

  4. A.

     rγ - 1

    B.

     1 - rγ - 1

    C.

     1 - (1/r) γ/γ - 1

    D.

     1 - (1/r) γ - 1/ γ

    View Answer

    Workspace

    Discuss Discuss in Forum


  5. A manufacturer claims to have a heat engine capable of developing 20 h.p. by receiving heat input of 400 kcal/mt and working between the temperature limits of 227° C and 27° C. His claim is

  6. A.

     Theoretically possible

    B.

     Not possible

    C.

     May be possible with lot of sophistications

    D.

     Cost will be very high

    View Answer

    Workspace

    Discuss Discuss in Forum


  7. Characteristic gas constant of a gas is equal to

  8. A.

     Cp /Cv

    B.

     Cv /Cp

    C.

     Cp - Cv

    D.

     Cp + Cv

    View Answer

    Workspace

    Discuss Discuss in Forum


  9. The variables which control the physical properties of a perfect gas are

  10. A.

     Pressure exerted by the gas

    B.

     Volume occupied by the gas

    C.

     Temperature of the gas

    D.

     All of these

    View Answer

    Workspace

    Discuss Discuss in Forum


  11. According to Avogadro's Hypothesis

  12. A.

     The molecular weights of all the perfect gases occupy the same volume under same conditions of pressure and temperature

    B.

     The sum of partial pressure of mixture of two gases is sum of the two

    C.

     Product of the gas constant and the molecular weight of an ideal gas is constant

    D.

     Gases have two values of specific heat

    View Answer

    Workspace

    Discuss Discuss in Forum


  13. The following cycle is used for air craft refrigeration

  14. A.

     Brayton cycle

    B.

     Joule cycle

    C.

     Carnot cycle

    D.

     Reversed Brayton cycle

    View Answer

    Workspace

    Discuss Discuss in Forum


  15. In closed cycle gas turbine, the air is compressed

  16. A.

     Isothermally

    B.

     Isentropically

    C.

     Polytropically

    D.

     None of these

    View Answer

    Workspace

    Discuss Discuss in Forum


  17. A perfect gas at 27°C is heated at constant pressure till its volume is double. The final temperature is

  18. A.

     54°C

    B.

     327°C

    C.

     108°C

    D.

     654°C

    View Answer

    Workspace

    Discuss Discuss in Forum


  19. The amount of heat required to raise the temperature of __________ water through one degree is called kilojoules.

  20. A.

     1 g

    B.

     10 g

    C.

     100 g

    D.

     1000 g

    View Answer

    Workspace

    Discuss Discuss in Forum