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Mechanical Engineering :: Hydraulics and Fluid Mechanics

  1. If V1 and V2 are the velocities of water at inlet and outlet of the draft tube respectively, then the efficiency of a draft tube is

  2. A.

     (V1 - V2) / V1

    B.

     (V1² - V2²) / V1²

    C.

     V1 / (V1 - V2)

    D.

     V1² / (V1² - V2²)


  3. The purpose of a surge tank is

  4. A.

     To control the pressure variations due to rapid changes in the pipe line flow

    B.

     To eliminate water hammer possibilities

    C.

     To regulate flow of water to turbines by providing necessary retarding head of water

    D.

     All of the above


  5. Center of buoyancy is the

  6. A.

     Centroid of the displaced volume of fluid

    B.

     Center of pressure of displaced volume

    C.

     Does not exist

    D.

     None of the above


  7. Bernoulli equation deals with the law of conservation of

  8. A.

     Mass

    B.

     Momentum

    C.

     Energy

    D.

     Work


  9. The hydraulic mean depth for a circular pipe of diameter (d) is

  10. A.

     d/6

    B.

     d/4

    C.

     d/2

    D.

     d


  11. Metacentre is the point of intersection of

  12. A.

     Vertical upward force through e.g. of body and center line of body

    B.

     Buoyant force and the center line of body

    C.

     Midpoint between e.g. and center of buoyancy

    D.

     All of the above


  13. Mercury does not wet glass. This is due to property of liquid known as

  14. A.

     Adhesion

    B.

     Cohesion

    C.

     Surface tension

    D.

     Viscosity


  15. With an increase in size of tube, the rise or depression of liquid in the tube due to surface tension will

  16. A.

     Decrease

    B.

     Increase

    C.

     Remain unchanged

    D.

     Depend upon the characteristics of liquid


  17. The relation between hydraulic efficiency (ηh), mechanical efficiency (ηm) and overall efficiency (ηo) is

  18. A.

     ηh = ηo × ηm

    B.

     ηm = ηm × ηh

    C.

     ηo = ηh × ηm

    D.

     None of these


  19. In open channels, the specific energy is the

  20. A.

     Total energy per unit discharge

    B.

     Total energy measured with respect to the datum passing through the bottom of the channel

    C.

     Total energy measured above the horizontal datum

    D.

     Kinetic energy plotted above the free surface of water