# DC Generator MCQs Quiz Multiple Choice Questions & Answers Page 2

## DC Generator Questions with Answers

51. The material for commutator brushes is generally

52. The terminal voltage of a series generator is 150 V when the load current is 5 A. If theload current is increased to 10 A, the terminal voltage will be

53. According to Flemings right-hand rule for finding the direction of induced e.m.f., when middle finger points in the direction of induced e.m.f., forefinger will point in the direction of

54. In the case of lap winding resultant pitch is

55. In a level compounded D.C. generator, full load terminal voltage is

56. Interpole flux should be sufficient to

57. Flashing the field of D.C. generator means

58. In case of D.C. machine winding, number of commutator segments is equal to

59. Number of tappings for each equilizer ring is equal to

60. A series generator can self-excite

61. Eddy currents are induced in the pole shoes of a D.C. machine due to

62. In a D.C. generator the number of mechanical degrees and electrical degrees will be the same when

63. A D.C. generator can be considered as

64. The armature of D.C. generator is laminated to

65. The demagnetising component of armature reaction in a D.C. generator

66. If a self excited D.C. generator after being installed, fails to build up on its first trial run, the first thing to do is to

67. Shunt generators are most suited for stable parallel operation because of their

68. In D.C. generators the pole shoes are fastened to the pole core by

69. In any rotating machine that part which houses the conductors and in which e.m.f.induced is to be utilised is called

70. In case of a 4-pole D.C. generator provided with a two layer lap winding with sixteen coils, the pole pitch will be

71. The essential condition for parallel operation of two D.C. generators is that they have

72. Which of the following generating machine will offer constant voltage on all loads ?

73. An exciter for a turbo generator is a

74. Following energized winding of a D.C. machine should not be opened as it wouldproduce high inductive voltage which may be dangerous to personnel and may cause itsown insulation failure.

75. Following D.C. generator will be in a position to build up without any residualmagnetism in the poles

76. D.C. generator generally preferred for charging automobile batteries is

77. Which of the following generator will have negligible terminal voltage while running onno-load ?

78. Which of the following D.C. generators will be in a position to build up without anyresidual magnetism in the poles ?

79. Which generator would you prefer for feeding long D.C. transmission lines ?

80. In D.C. generators, the cause of rapid brush wear may be

81. Which of the following generators will be preferred if they are required to be run inparallel ?

82. In D.C. generators on no-load, the air gap flux distribution in space is

83. For both lap and wave windings, there are as many commutator bars as the number of

84. Iron losses in a D.C. machine are independent of variations in

85. Two D.C. shunt generators, each with armature resistance of 0.02 ohm and fieldresistance of 50 ohm run in parallel and supply a total current of 1000 amperes to the loadcircuit. If their e.m.fs. are 270 V and 265 V, their bus bar voltage will be

86. The number of brushes in a commutator depends on

87. Two generators are running in parallel. One of the generators may run as motor forwhich of the following reasons ?

88. The main factor which leads to unstable parallel operation of flat and over compounded generators is

89. In a D.C. generator the magnetic neutral axis coincides with the geometrical neutralaxis, when

90. D.C. generators are connected to the busbars or disconnected from them only under thefloating condition

91. When two D.C. generators are running in parallel an equilizer bar is used

92. When two D.C. series generators are running in parallel, an equilizer bar is used

93. The purpose of providing dummy coils in a generator is

94. The function of pole shoes in the case of D.C. machine is

95. D.C. series generator is used

96. In a D.C. machine stray loss is the sum of

97. As a result of armature reaction, the reduction in the total mutual air gap flux in a D.C.generator is approximately

98. In a D.C. generator the ripples in the direct e.m.f. generated are reduced by

99. In case of a flat compounded generator

100. For the parallel operation of two or more D.C. compound generators, we should ensurethat