Power Electronics MCQ

Test your knowledge with important Power Electronics MCQ and their applications. These MCQs are beneficial for competitive exams too. Explore 30 + more Power Electronics MCQs at Bissoy

• A triac is equivalent to two SCRs ___________.
  ক

  In parallel

  খ

  In series

  গ

  In inverse-parallel

  ঘ

  None of the above
• The triac is ___________.
  ক

  Like a bidirectional SCR

  খ

  A four-terminal device

  গ

  Not a thyristor

  ঘ

  None of the above
• When a UJT is turned ON, the resistance between emitter terminal and lower base terminal ___________
  ক

  Remains the same

  খ

  Is decreased

  গ

  Is increased

  ঘ

  None of the above
• A diac has ___________ semiconductor layers
  ক

  Three

  খ

  Two

  গ

  Four

  ঘ

  None of the above
• A triac has ___________ semiconductor layers.
  ক

  Two

  খ

  Three

  গ

  Four

  ঘ

  Five
• A diac is simply ___________.
  ক

  A single junction device

  খ

  A three junction device

  গ

  A triac without gate terminal

  ঘ

  None of the above
• A DIAC is ___________ switch.
  ক

  An a.c.

  খ

  A d.c.

  গ

  A mechanical

  ঘ

  None of the above
• Power electronics essentially deals with control of a.c. power at ___________.
  ক

  Frequencies above 20 kHz

  খ

  Frequencies above 1000 kHz

  গ

  Frequencies less than 10 Hz

  ঘ

  50 Hz frequency
• When the temperature increases, the inter-base resistance (RBB) of a UJT ___________.
  ক

  Increases

  খ

  Decreases

  গ

  Remains the same

  ঘ

  None of the above
• A Triac has three terminals viz ___________
  ক

  Drain, source, gate

  খ

  Two main terminal and a gate terminal

  গ

  Cathode, anode, gate

  ঘ

  None of the above
• The V-I characteristics for a triac in the first and third quadrants are essentially identical to those of ___________ in its first quadrant
  ক

  Transistor

  খ

  SCR

  গ

  UJT

  ঘ

  none of the above
• The device that does not have the gate terminal is ___________.
  ক

  Triac

  খ

  FET

  গ

  SCR

  ঘ

  Diac
• In a UJT, the p-type emitter is ___________ doped
  ক

  Lightly

  খ

  Heavily

  গ

  Moderately

  ঘ

  None of the above
• When the temperature increases, the intrinsic stand off ratio ___________.
  ক

  Increases

  খ

  Decreases

  গ

  Essentially remains the same

  ঘ

  None of the above
• When the emitter terminal of a UJT is open, the resistance between the base terminal is generally ___________.
  ক

  High

  খ

  Low

  গ

  Extremely low

  ঘ

  None of the above
• The device that exhibits negative resistance region is ___________.
  ক

  Diac

  খ

  Triac

  গ

  Transistor

  ঘ

  UJT
• A diac is turned on by ___________.
  ক

  A breakover voltage

  খ

  Gate voltage

  গ

  Gate current

  ঘ

  None of the above
• A UJT is sometimes called ___________ diode.
  ক

  Low resistance

  খ

  High resistance

  গ

  Single-base

  ঘ

  Double-base
• To turn on UJT, the forward bias on the emitter diode should be ___________ the peak point voltage.
  ক

  Less than

  খ

  Equal to

  গ

  More than

  ঘ

  None of the above
• After peak point, the UJT operates in the ___________ region.
  ক

  Cut-off

  খ

  Saturation

  গ

  Negative resistance

  ঘ

  None of the above
• Between the peak point and the valley point of UJT emitter characteristics we have ___________ region
  ক

  Saturation

  খ

  Negative resistance

  গ

  Cut-off

  ঘ

  None of the above
• A triac can pass a portion of ___________ half-cycle through the load.
  ক

  Only positive

  খ

  Only negative

  গ

  Both positive and negative

  ঘ

  None of the above
• Which of the following is not a characteristic of UJT?
  ক

  Intrinsic stand off ratio

  খ

  Negative resistance

  গ

  Peak-point voltage

  ঘ

  Bilateral conduction
• The normal way to turn on a diac is by ___________.
  ক

  Gate current

  খ

  Gate voltage

  গ

  Breakover voltage

  ঘ

  None of the above
• A triac is a ___________ switch
  ক

  Bidirectional

  খ

  Unidirectional

  গ

  Mechanical

  ঘ

  None of the above
• A diac has ___________ terminals.
  ক

  Two

  খ

  Three

  গ

  Four

  ঘ

  None of the above
• A diac has ___________ pn junctions
  ক

  Four

  খ

  Two

  গ

  Three

  ঘ

  None of the above
• The UJT may be used as ___________.
  ক

  Am amplifier

  খ

  A sawtooth generator

  গ

  A rectifier

  ঘ

  None of the above
• A UJT has ___________.
  ক

  Two pn junctions

  খ

  One pn junction

  গ

  Three pn junctions

  ঘ

  None of the above
• Determine the loss in the snubber circuit, if C = 0.545 μF and supply is 200 V, 10 kHz.
  ক

  233 W

  খ

  133 W

  গ

  333 W

  ঘ

  233 W