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  • Question

  • Assertion (A): The phenomenon of differential mobility is called transferred electron effect.

    Reason (R): GaAs exhibits transferred electron effect.


  • Options
  • A. Both A and R are correct and R is correct explanation of A
  • B. Both A and R are correct but R is not correct explanation of A
  • C. A is correct but R is wrong
  • D. A is wrong but R is correct

  • Correct Answer
  • Both A and R are correct but R is not correct explanation of A 

    Explanation
    A Gunn diode uses GaAs which has a negative differential mobility, i.e., a decrease in carrier velocity with increase in electric field.

    This effects is called transferred electron effect. The impedance of a Gunn diode is tens of ohms.

    A Gunn diode oscillator has a resonant cavity, an arrangement to couple Gunn diode to cavity, biasing arrangement for Gunn diode and arrangement to couple RF power to load.

    Applications of Gunn diode oscillator include continuous wave radar, pulsed radar and microwave receivers.

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    • Options
    • A. waits for positive or negative acknowled-gement from the receiving terminal after sending a block
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    • Options
    • A. 0
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    • C. 0.7 V across each depletion layer
    • D. 0.35 V
      • Discuss
    • 4. Induction heating systems require low frequency inverters.

    • Options
    • A. True
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    • A. True
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    • Options
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    • Options
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    • Options
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      • Discuss
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    • Options
    • A. It is a unidirectional voltage
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    • Options
    • A. True
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