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  • Question

  • An amplifier without feedback has a voltage gain of 50, input resistance of 1 k? and output resistance of 2.5 k?. The input resistance of the current shunt -ve feedback amplifier using the above amplifier with a feedback factor of 0.2 is


  • Options
  • A. 1/11 k?
  • B. 1/5 k?
  • C. 5 kW
  • D. 11 kW

  • Correct Answer
  • 1/11 k? 

    Explanation
    Input Resistance with feedback for current shunt, An amplifier without feedback has a voltage gain of 50, input resistance of 1 k? and output resistan.

    More questions

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    • Options
    • A. of the same magnitude
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    • Options
    • A. 1000 MHz
    • B. 5000 MHz
    • C. 14000 MHz
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    • 3. In a radio receiver

    • Options
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    • 4. As compared to an ordinary semiconductor diode, a Schottky diode

    • Options
    • A. has higher reverse saturation current
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    • C. has higher reverse saturation current and lower cut in voltage
    • D. has lower reverse saturation current and lower cut in voltage
      • Discuss
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    • Options
    • A.
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    • Options
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    • 7. A standard cell of 1.0185 V is used with a slide wire potentiometer. The balance was obtained at 60 cm. When an unknown emf was connected, the balance was obtained at 82 cm. The magnitude of unknown emf is

    • Options
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    • Options
    • A. 5
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      Reason (R): A DIAC can conduct in both directions.


    • Options
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    • B. Both A and R correct but R is not correct explanation of A
    • C. A is correct but R is wrong
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      • Discuss
    • 10. A NAND gate has 3 inputs and one output. The number of thyristors required for this gate are

    • Options
    • A. 1
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