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  • Question
  • If the Francis turbine is run below 50 percent head for a long period, it will not only lose its efficiency but also the cavitation danger will become more serious.


  • Options
  • A. Agree
  • B. Disagree

  • Correct Answer
  • Agree 


  • Hydraulic Machines problems


    Search Results


    • 1. If the ratio's of the corresponding forces acting at corresponding points are equal, then the model and the prototype are said to have.

    • Options
    • A. geometric similarity
    • B. kinematic similarity
    • C. dynamic similarity
    • D. none of these
    • Discuss
    • 2. Dynamic similarity is said to exist between the model and the prototype, if both of them

    • Options
    • A. have identical velocities
    • B. are equal in size and shape
    • C. are identical in shape, but differ only in size
    • D. none of the above
    • Discuss
    • 3. The cavitation in reaction turbines is avoided, to a great extent by

    • Options
    • A. installing the turbine below the tail race level
    • B. using stainless steel runner of the turbine
    • C. providing highly polished blades to the runner
    • D. all of the above
    • Discuss
    • 4. In a mixed flow centrifugal pump, the flow through the impeller is a combination of radial and axial flows.

    • Options
    • A. Correct
    • B. Incorrect
    • Discuss
    • 5. A Kaplan turbine is an axial flow reaction turbine.

    • Options
    • A. Correct
    • B. Incorrect
    • Discuss
    • 6. 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

    • Options
    • A.
    • B.
    • C.
    • D.
    • Discuss
    • 7. The hydraulic efficiency of an impulse turbine is maximum when velocity of wheel is __________ of the jet velocity,

    • Options
    • A. one-fourth
    • B. one-half
    • C. three-fourth
    • D. double
    • Discuss
    • 8. A hydraulic intensifier is a device used to increase the intensity of pressure of water by means of energy available from a large quantity of water at a low pressure.

    • Options
    • A. Correct
    • B. Incorrect
    • Discuss
    • 9. Which of the following statement is correct as regard to water wheels?

    • Options
    • A. They have slow speeds.
    • B. They are suitable even for low water heads.
    • C. They give constant efficiency, even if the discharge is not constant
    • D. all of the above
    • Discuss
    • 10. The hydraulic efficiency of an impulse turbine is the

    • Options
    • A. ratio of the actual power produced by the turbine to the energy actually supplied by the turbine
    • B. ratio of the actual work available at the turbine to the energy imparted to the wheel
    • C. ratio of the work done on the wheel to the energy of the jet
    • D. none of the above
    • Discuss


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