Quiznetik

Fluid Mechanics (FM) | Set 6

1. The movement of ships and boats in water is due to

Correct : B. Jet propulsion

2. The inlet orifices are at what angle with the motion of the ship?

Correct : D. 90

3. Which among the following is a formula for force when it acts perpendicular to the direction of flow?

Correct : A. pav2 SinθCosθ

4. Which among the following is the formula for relative velocity?

Correct : A. V + u

5. Component of velocity in direction of jet is -VCosθ. What does ‘θ’ indicate?

Correct : C. Angle made by jet and inlet tip

6. Principle of fluid mechanics works on the utilization of

Correct : C. Work

7. The force analysis on a curved vane is understood using

Correct : A. Velocity triangles

8. How is absolute velocity at inlet denoted?

Correct : B. V1

9. The relative velocity is obtained by the equation

Correct : A. u – V1

10. If the friction is neglected, then

Correct : C. Vr1 = Vr2

11. If the pressure remains a constant, then

Correct : C. Vr1 = Vr2

12. Jet propulsion of ship is less efficient than screw propeller due to

Correct : C. Frictional losses

13. Jet propulsion of ship in a very shallow water is needed to

Correct : B. Avoid damage of the propeller

14. A turbojet does not consist of which of the following component?

Correct : D. Air filter

15. Which among the following is not a type of jet engine?

Correct : D. Propulsive jet

16. Hydraulic energy is converted into another form of energy by hydraulic machines. What form of energy is that?

Correct : A. Mechanical Energy

17. Which principle is used in Hydraulic Turbines?

Correct : B. Newton’s second law

18. Buckets and blades used in a turbine are used to:

Correct : A. Alter the direction of water

19. is the electric power obtained from the energy of the water.

Correct : D. Hydroelectric power

20. Which energy generated in a turbine is used to run electric power generator linked to the turbine shaft?

Correct : A. Mechanical Energy

21. Hydraulic Machines fall under the category :

Correct : D. Roto-dynamic machinery

22. Which kind of turbines changes the pressure of the water entered through it?

Correct : A. Reaction turbines

23. Which type of turbine is used to change the velocity of the water through its flow?

Correct : C. Impulse turbines

24. Which type of turbine is a Francis Turbine?

Correct : C. Reaction turbine

25. How many types of Reaction turbines are there?

Correct : A. 5

26. Maximum Number of jets, generally, employed in an impulse turbine without jet interference can be?

Correct : D. 6

27. The overall efficiency of a reaction turbine is the ratio of

Correct : A. Actual work available at the turbine to the energy imparted to the wheel

28. In a reaction turbine, the draft tube is used to

Correct : A. To increase the head of water by an amount that is equal to the height of the runner outlet above the tail race

29. In reaction turbine hydraulic efficiency is_

Correct : B. Ratio of work done on the wheel to energy that is supplied to the turbine.

30. Consider an inward flow reaction turbine, here, water

Correct : B. Enters the wheel at the outer periphery and then flows towards the centre of the wheel

31. The working of which of the following hydraulic units is based on Pascal’s law?

Correct : C. Hydraulic press

32. Which kind of turbine is a Pelton Wheel turbine?

Correct : A. Tangential flow turbine.

33. IN what type of turbine water enters in radial direction and leaves axial direction?

Correct : D. Mixed flow turbine

34. How many types of turbines can you classify on the basis of direction of flow through runner?

Correct : C. 4

35. Into how many types can you classify radial flow turbines?

Correct : D. 2

36. Into how many types can you classify turbines on basis of head at inlet?

Correct : A. 3

37. Among the following which turbine requires more head?

Correct : A. Pelton Turbine

38. Total head of turbines is_

Correct : D. Pressure head + Kinetic head + Static head

39. Head under which Kaplan turbine is operated

Correct : A. 10-70 meters

40. Head under which Francis turbine is operated

Correct : D. 40 -600 meters

41. The turbine is preferred for 0 to 25 m head of water?

Correct : B. Kaplan turbine

42. Under what head is Pelton turbine operated?

Correct : B. 15-2000 meters

43. is difference between head race and tail race

Correct : A. Gross head

44. The head available at inlet of turbine

Correct : C. Net head

45. Head lost due to friction is given by k*f*L*v*v/D*2g where f- friction coefficient, L- length of pen stock, D- diameter of penstock and” k” is constant and its value is

Correct : C. 4

46. The difference between gross head and friction losses is

Correct : A. Net head

47. is defined as ratio between power delivered to runner and power supplied at inlet of turbine.

Correct : C. Hydraulic efficiency

48. Which among the following which is not an efficiency of turbine?

Correct : D. Electrical efficiency

49. The ratio of power at the shaft of turbine and power delivered by water to runner is known as?

Correct : A. Mechanical efficiency

50. The product of mechanical efficiency and hydraulic efficiency is known as?

Correct : D. Overall efficiency

51. Among the following which turbine has highest efficiency?

Correct : A. Kaplan turbine

52. In the expression for overall efficiency of turbine, which is p/(k*g*q*h), where “k” is known as

Correct : A. Density of liquid

53. The expression for maximum hydraulic efficiency of pelton turbine is given by?

Correct : A. (1+cos k)/2 where k is outlet blade angle

54. To obtain maximum hydraulic efficiency of pelton turbine, blade velocity should be                      Times the inlet velocity of jet.

Correct : A. Half

55. Among the following which turbine has least efficiency?

Correct : A. Pelton turbine

56. A hydraulic coupling belongs to the category of

Correct : D. Energy transfer machines

57. The electric power which is obtained from hydraulic energy

Correct : D. Hydroelectric power

58. At present which is cheapest means of generating power_

Correct : C. Hydroelectric power

59. Pipes of largest diameter which carry water from reservoir to the turbines is known as_

Correct : D. Pen stock

60. Pen stocks are made up of

Correct : A. Steel

61. is an inward radial flow reaction turbine?

Correct : C. Francis turbine

62. The important type of axial flow reaction turbines are

Correct : D. Propeller and Kaplan turbines

63. is a axial flow reaction turbines, if vanes are fixed to hub of turbine

Correct : A. Propeller turbine

64. Francis and Kaplan turbines are known as

Correct : B. Reaction turbine

65. Specific speed of reaction turbine is between?

Correct : B. 10 and 100

66. Impulse turbine is generally fitted at

Correct : B. Above the tail race

67. Hydraulic turbines are classified based on

Correct : D. Energy available, Direction of flow, Head at inlet.

68. Impulse turbine and reaction turbine are classified based on ?

Correct : A. Type of energy at inlet

69. Tangential flow, axial flow, radial flow turbines are classified based on?

Correct : B. Direction of flow through runner

70. High head, low head and medium head turbines are classified based on

Correct : C. Head at inlet of turbine

71. Low specific speed, high specific speed and medium specific speed are classified based on

Correct : D. Specific speed of turbine

72. If energy available at inlet of turbine is only kinetic energy then it is classified based on

Correct : A. Type of energy at inlet

73. If water flows in radial direction at inlet of runner and leaves axially at outlet then turbine is named as

Correct : D. Mixed flow turbine

74. Pelton turbine is operated under

Correct : B. High head and low discharge

75. Kaplan turbine is operated under

Correct : A. Low head and high discharge

76. Medium specific speed of turbine implies

Correct : C. Francis turbine

77. High specific speed of turbine implies that it is_

Correct : D. Kaplan turbine

78. Velocity triangles are used to analyze

Correct : D. Flow of water, measure of discharge, angle of deflection.

79. In which of following turbine inlet and outlet blade velocities of vanes are equal?

Correct : C. Pelton turbine

80. Tangential velocity of blade of Pelton wheel is proportional to

Correct : A. Speed of wheel

81. In which of following turbine inlet whirl velocity and inlet jet velocity are equal in magnitude?

Correct : A. Pelton turbine

82. In Pelton wheel, if outlet velocity angle of jet is “acute angled” then outlet whirl velocity of jet is

Correct : A. x- component of V(r2) – blade velocity

83. In Pelton wheel, if outlet velocity angle of jet is “obtuseangled” then outlet whirl velocity of jet is

Correct : C. Blade velocity – x- component of V (r2)

84. In Pelton wheel, if outlet velocity angle of jet is “right angled” then outlet whirl velocity of jet is

Correct : D. Zero

85. In Pelton wheel, relative inlet velocity of jet with respect to velocity of vane is

Correct : A. Difference between inlet jet velocity and blade velocity

86. In Pelton wheel if angle of deflection is not mentioned then we assume it as_

Correct : C. 165 degrees

87. The work done per unit weight of water jet striking runner blades of Pelton turbine is given by expression

Correct : A. [Vw1+Vw2] u/g

88. In Pelton turbine the energy available at inlet of runner that is at outlet of nozzle is known as

Correct : B. Runner power

89. In Pelton turbines the expression for power delivered at inlet to runner is given by

Correct : C. W*[Vw1+Vw2]u/g, W*[Vw1-Vw2]u/g

90. Calculate work done by jet per second on the runner where, discharge=0.7cubic meters/s, inlet and outlet whirl velocities be 23.77 and 2.94?

Correct : C. 187Kw

91. 10.The expression for water power in Pelton wheel is

Correct : A. (P*g*Q*H) Kw

92. The hydraulic efficiency of Pelton turbine will be maximum when blade velocity is equal to

Correct : A. V/2

93. In Pelton turbine is defined as ratio between power delivered to runner and power supplied at inlet of turbine

Correct : C. Hydraulic efficiency

94. In Pelton turbine product of mechanical efficiency and hydraulic efficiency is known as

Correct : D. Overall efficiency

95. In Pelton is ratio of volume of water actually striking the runner and volume of water supplied to turbine?

Correct : B. Volumetric efficiency

96. In Pelton turbine the ratio of volume available at shaft of turbine and power supplied at the inlet of the turbine is

Correct : D. Overall efficiency

97. The expression for maximum hydraulic efficiency of Pelto turbine is given by

Correct : A. (1+cos k)/2 where k is outlet blade angle

98. In the expression for overall efficiency of turbine, which is p/ (k*g*q*h), where “k” is known as

Correct : B. Density of liquid

99. Design of Pelton wheel means the following data is to be determined.

Correct : D. All of the mentioned

100. The width of buckets of Pelton wheel is

Correct : D. 5 times diameter of jet