Hydraulic Machines Multiple Choice Questions and Answers

31. The discharge through a reaction turbine with increase in unit speed

1. increases
2. decreases
3. remains unaffected
4. first increases and then decreases

32. Francis, Kaplan and propeller turbines fall under the category of

1. Impulse turbines
2. Reaction turbines
3. Axial flow turbines
4. Mixed flow turbines

33. Head developed by a centrifugal pump depends on

1. impeller diameter
2. speed
3. fluid density
4. a and b above

34. When a piping system is made up primarily of vertical lift and very little pipe friction, the pump characteristics should be

1. horizontal
2. nearly horizontal
3. steep
4. first rise and then fall

35. When a piping system is made up primarily of friction head and very little of vertical lift, then pump characteristics should be

1. horizontal
2. nearly horizontal
3. steep
4. first rise and then fall

36. Reciprocating pumps are no more to be seen in industrial applications (in comparison to centrifugal pumps) because of

1. high initial and maintenance cost
2. lower discharge
3. lower speed of operation
4. necessity of air vessel

37. Multistage centrifugal pumps are used to obtain

1. high discharge
2. high head
3. pumping of viscous fluids
4. high head and high discharge

38. The angle of taper on draft tube is

1. greater than 15 degree
2. greater than 8 degree
3. greater than 5 degree
4. less than 8 degree

39. Multi stage centrifugal pumps are used to

1. Give high discharge
2. Produce high heads
3. Pump viscous fluids
4. All the above

40. Runaway speed of a hydraulic turbine is

1. full load speed
2. the speed at which turbine runner will be damaged
3. the speed if the turbine runner is allowed to revolve freely without load and with the wicket gates wide open
4. the speed corresponding to maximum overload permissible