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  • Question
  • The efficiency of a reaction turbine for a given head __________ with the increase in speed.


  • Options
  • A. decreases
  • B. increases

  • Correct Answer
  • decreases 


  • Hydraulic Machines problems


    Search Results


    • 1. The ratio of the normal force of jet of water on a plate inclined at an angle of 30° as compared to that when the plate is normal to jet, is

    • Options
    • A. 1/2
    • B. 1/2
    • C. 1
    • D. 2
    • Discuss
    • 2. Which of the following statement is wrong?

    • Options
    • A. The reaction turbines are used for low head and high discharge.
    • B. The angle of taper on draft tube is less than 8°.
    • C. An impulse turbine is generally fitted slightly above the tail race.
    • D. A Francis turbine is an impulse turbine.
    • Discuss
    • 3. 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
    • 4. 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
    • 5. 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
    • 6. Which of the following pump is successfully used for lifting water from deep wells?

    • Options
    • A. Centrifugal pump
    • B. Reciprocating pump
    • C. Jet pump
    • D. Air lift pump
    • Discuss
    • 7. A double overhung Pelton wheel has

    • Options
    • A. two jets
    • B. two runners
    • C. four jets
    • D. four runners
    • Discuss
    • 8. Mechanical efficiency of a centrifugal pump is the ratio of

    • Options
    • A. energy available at the impeller to the energy supplied to the pump by the prime mover
    • B. actual workdone by the pump to the energy supplied to the pump by the prime mover
    • C. energy supplied to the pump to the energy available at the impeller
    • D. manometric head to the energy supplied by the impeller per kN of water
    • Discuss
    • 9. The specific speed (Ns) of a centrifugal pump is given by

    • Options
    • A.
    • B.
    • C.
    • D.
    • Discuss
    • 10. Which of the following turbine is preferred for a specific speed of 60 to 300 r.p.m.?

    • Options
    • A. Pelton wheel
    • B. Francis turbine
    • C. Kaplan turbine
    • D. none of these
    • Discuss


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