Home / Mechanical Engineering / Internal Combustion Engines :: section-1

Mechanical Engineering :: Internal Combustion Engines

  1. The two reference fuels used for cetane rating are

  2. A.

     Cetane and iso-octane

    B.

     Cetane and alpha-methyl naphthalene

    C.

     Cetane and normal heptane

    D.

     Cetane and tetra ethyl lead

    View Answer

    Workspace

    Discuss Discuss in Forum


  3. For the same power developed in I.C. engines, the cheaper system is

  4. A.

     Naturally aspirated

    B.

     Supercharged

    C.

     Centrifugal pump

    D.

     Turbo charger

    View Answer

    Workspace

    Discuss Discuss in Forum


  5. As compared to air standard cycle, in actual working, the effect of variation in specific heats is to

  6. A.

     Increase maximum pressure and maximum temperature

    B.

     Reduce maximum pressure and maximum temperature

    C.

     Increase maximum pressure and decrease maximum temperature

    D.

     Decrease maximum pressure and increase maximum temperature

    View Answer

    Workspace

    Discuss Discuss in Forum


  7. The expansion of fuel in a four stroke cycle diesel engine

  8. A.

     Starts at 15° before top dead center and ends at 30° after top dead center

    B.

     Starts at top dead center and ends at 30° after top dead center

    C.

     Starts at 15° after top dead center and ends at 30° before bottom dead center

    D.

     May start and end anywhere

    View Answer

    Workspace

    Discuss Discuss in Forum


  9. The fuel valve in a four stroke cycle diesel engine

  10. A.

     Opens at 15° after top dead center and closes at 20° before bottom dead center

    B.

     Opens at 15° before top dead center and closes at 20° after top dead center

    C.

     Opens at top dead center and closes at bottom dead center

    D.

     May open and close anywhere

    View Answer

    Workspace

    Discuss Discuss in Forum


  11. In a typical medium speed, 4-stroke cycle diesel engine

  12. A.

     Fuel injection starts at 10° before top dead center and ends at 20° after top dead center

    B.

     Fuel injection starts at top dead center and ends at 20° after top dead center

    C.

     Fuel injection starts at just before top dead center and ends just after top dead center

    D.

     May start and end anywhere

    View Answer

    Workspace

    Discuss Discuss in Forum


  13. In a typical medium speed 4-stroke cycle diesel engine

  14. A.

     Compression starts at 35° after bottom dead center and ends at top dead center

    B.

     Compression starts at bottom dead center and ends at top dead center

    C.

     Compression starts at 10° before bottom dead center and, ends just before top dead center

    D.

     May start and end anywhere

    View Answer

    Workspace

    Discuss Discuss in Forum


  15. The exhaust valve in a four stroke cycle petrol engine

  16. A.

     Opens at 50° before bottom dead center and closes at 15° after top dead center

    B.

     Opens at bottom dead center and closes at top dead center

    C.

     Opens at 50° after bottom dead center and closes at 15° before top dead center

    D.

     May open and close anywhere

    View Answer

    Workspace

    Discuss Discuss in Forum


  17. For the same compression ratio

  18. A.

     Otto cycle is more efficient than the Diesel

    B.

     Diesel cycle is more efficient than Otto

    C.

     Both Otto and Diesel cycles are, equally efficient

    D.

     Compression ratio has nothing to do with efficiency

    View Answer

    Workspace

    Discuss Discuss in Forum


  19. The ratio of the brake power to the indicated power is called

  20. A.

     Mechanical efficiency

    B.

     Overall efficiency

    C.

     Indicated thermal efficiency

    D.

     Volumetric efficiency

    View Answer

    Workspace

    Discuss Discuss in Forum