# Home / Mechanical Engineering / Hydraulic Machines :: Section 1

### Mechanical Engineering :: Hydraulic Machines

1. Power required to drive a centrifugal pump is directly proportional to __________ of its impeller.

2.  A. diameter B. square of diameter C. cube of diameter D. fourth power of diameter   3. The mechanical efficiency of an impulse turbine is

4.  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   5. The overshot water wheels are those in which the wheel runs entirely by the __________ of water.

6.  A. weight B. impulse   7. In a Kaplan turbine runner, the number of blades are generally between

8.  A. 2 to 4 B. 4 to 8 C. 8 to l6 D. 16 to 24   9. If Hg is the gross or total head and hf is the head lost due to friction, then net or effective head (H) is given by

10.  A. H = Hg/hf B. H = Hg x hf C. H = Hg + hf D. H = Hg - hf   11. Discharge of a centrifugal pump is

12.  A. directly proportional to diameter of its impeller B. inversely proportional to diameter of its impeller C. directly proportional to (diameter)2 of its impeller D. inversely proportional to (diameter)2 of its impeller   13. A Pelton wheel develops 1750 kW under a head of 100 metres while running at 200 r.p.m. and discharging 2500 litres of water per second. The unit power of the wheel is

14.  A. 0.25 kW B. 0.75 kW C. 1.75 kW D. 3.75 kW   15. The static head of a centrifugal pump is equal to the __________ of suction head and delivery head.

16.  A. product B. difference C. sum   17. The ratio of actual work available at the turbine to the energy imparted to the wheel is known as __________ efficiency.

18.  A. hydraulic B. mechanical C. overall   19. Geometric similarity is said to exist between the model and the prototype, if both of them

20.  A. have identical velocities B. are equal in size and shape C. are identical in shape, but differ only in size D. have identical forces   