Electronics MCQ Question and Answer

Electronics MCQ Question and Answer
1. For a common emitter circuit if IC/IE = 0.98 then current gain for common emitter circuit will be
  • 49
  • 98
  • 4.9
  • 25.5
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2. In a p-n junction
  • The potential of the p and n sides becomes higher alternately
  • The p side is at higher electrical potential than the n side
  • The n side is at higher electrical potential than the p side
  • Both the p and n sides are at the same potential
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3. In the case of a common emitter transistor amplifier the ratio of the collector current to the emitter current Ic/Ie is 0.96. The current gain of the amplifier is ?
  • 6
  • 48
  • 24
  • 12
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4. if a full wave rectifier circuit is operating from 5oHz mains, the fundamental frequency in the
tipple will be
  • 100Hz
  • 25Hz
  • 50Hz
  • 70.7 Hz
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5. A n-p-n transistor conducts when ?
  • both collector and emitter are negative with respect to, the base
  • both collector and emitter are positive with respect to the base
  • collector is positive and emitter is negative with to the base
  • collector is positive and emitter is at same potential as the base
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6. Barrier potential of a p-n junction diode does not depend on?
  • doping density
  • diode design
  • temperature
  • forward bias
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7. Reverse bias applied to a junction diode
  • increases the minority carrier current
  • lowers the potential barrier
  • raises the potential barrier
  • increases the majority carrier current
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8. In semiconductors at a room temperature

  • the conduction band is completely empty
  • the valence band is partially empty and the conduction band is partially filled
  • the valence band is completely filled and the conduction band is partially filled
  • the valence band is completely filled
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9. The output of OR gate is 1 when?
  • if either input is zero
  • if both inputs are zero
  • if either or both inputs are 1
  • only if both inputs are I
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10. In a p-n junction photo cell, the value of the photo-electromotive force produced by monochromatic light is proportional to ?
  • the voltage applied at the p-n junction
  • the barrier voltage at the p-n junction
  • the intensity of the light falling on the cell
  • the frequency of the light falling on the cell
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