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Mechanical Engineering :: Steam Nozzles and Turbines

  1. The number of water level indicators in a boiler are generally __________ in number.

  2. A.

     One

    B.

     Two

    C.

     Three

    D.

     Four


  3. The fire tubes in a Cochran boiler usually have _________ diameter.

  4. A.

     6.25 mm

    B.

     62.5 mm

    C.

     72.5 mm

    D.

     92.5 mm


  5. The fire tubes in a Locomotive boiler has __________ diameter.

  6. A.

     4.75 mm

    B.

     5.47 mm

    C.

     7.45 mm

    D.

     47.5 mm


  7. Which of the following is correct? (Where pa = Actual mean effective pressure, pm = Theoretical mean effective pressure, and K = Diagram factor)

  8. A.

     pa = pm/K

    B.

     pa = pm × K

    C.

     pa = K/pm

    D.

     pa = pm + K


  9. The critical pressure ratio (p₂/p₁) is given by

  10. A.

     (p₂/p₁) = [2/(n - 1)] n/(n + 1)

    B.

     (p₂/p₁) = [2/(n + 1)] n/(n-1)

    C.

     (p₂/p₁) = [(n - 1)/2] n + (1/n)

    D.

     (p₂/p₁) = [(n + 1)/2] n - (1/n)


  11. The main object of a boiler trial is

  12. A.

     To determine the generating capacity of the boiler

    B.

     To determine the thermal efficiency of the boiler when working at a definite pressure

    C.

     To prepare heat balance sheet for the boiler

    D.

     All of the above


  13. The pressure of feed water has to be raised before its entry into the boiler. The pressure is raised by a device known as

  14. A.

     Feed pump

    B.

     Injector

    C.

     Feed check valve

    D.

     Pressure gauge


  15. The function of a safety valve is

  16. A.

     To blow off steam when the pressure of steam inside the boiler exceeds the working pressure

    B.

     To indicate the water level inside the boiler to an observer

    C.

     To measure pressure of steam inside the steam boiler

    D.

     None of the above


  17. The function of a piston in a steam engine is

  18. A.

     To guide motion of the piston rod and to prevent it from bending

    B.

     To transfer motion from the piston to the cross-head

    C.

     To convert heat energy of the steam into mechanical work id) to exhaust steam from the cylinder at proper moment

    D.

     None of these


  19. Adiabatic process is

  20. A.

     Essentially an isentropic process

    B.

     Non-heat transfer process

    C.

     Reversible process

    D.

     Constant temperature process