Power Electronics MCQ Questions and Answers Quiz

81. A triac is a …………. switch

  1. Unidirectional
  2. Mechanical
  3. Bidirectional
  4. None of the above

82. A triac is equivalent to two SCRs …………..

  1. In series
  2. In inverse-parallel
  3. In parallel
  4. None of the above

83. A UJT has ……………….

  1. One pn junction
  2. Three pn junctions
  3. Two pn junctions
  4. None of the above

84. A UJT is sometimes called …………. diode

  1. High resistance
  2. Single-base
  3. Low resistance
  4. Double-base

85. AC power in a load can be controlled by using

  1. two SCRs in series
  2. three SCRs in series
  3. two SCRs in parallel opposition
  4. four SCRs in series

86. After peak point, the UJT operates in the ……………. region

  1. Saturation
  2. Negative resistance
  3. Cut-off
  4. None of the above

87. An SCR can be used

  1. for power control
  2. for speed control of dc shunt motor
  3. as static conductor
  4. all of these

88. An SCR is made up of silicon because

  1. silicon has small leakage current than germanium
  2. silicon has small leakage voltage than germanium
  3. silicon has large leakage current than germanium
  4. silicon has large leakage voltage than germanium

89. Between the incoming and outgoing devices in voltage commutation

  1. Small overlapping operation
  2. No overlapping operation
  3. Large overlapping takes place
  4. None of these

90. Between the peak point and the valley point of UJT emitter characteristics we have ………….. region

  1. Negative resistance
  2. Cut-off
  3. Saturation
  4. None of the above

MCQ Multiple Choice Questions and Answers on Power Electronics

Power Electronics Question and Answer