Power Electronics MCQ Questions and Answers Quiz

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

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

82. A UJT has ……………….

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

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

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

84. 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

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

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

86. 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

87. 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

88. 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

89. 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

90. Double fourier series analysis of PWM is

  1. Three dimensional functions
  2. One dimensional functions
  3. Two dimensional functions
  4. All of these

MCQ Multiple Choice Questions and Answers on Power Electronics

Power Electronics Question and Answer