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Homework Help: Electronics questions - help needed

  1. Mar 1, 2012 #1
    Electronics questions -- help needed

    1. The problem statement, all variables and given/known data

    Revered members,
    I list below some of the questions asked in a competitive exam to test the proficiency of electronics. I request the members to give the answers. I have produced the answers which i have written, below each question. I require your help in ascertaining if they are correct.
    An oscillator differs from an amplifier , because it
    a) has more gain b) requires no input signal c) requires no DC supply d) always has the same input
    Ans: requires no input signal
    Which of the following devices has the highest input impedance
    a) JFET b) MOSFET C) Crystal Diode d) Ordinary transistor
    Ans : Ordinary Transistor
    Which of the following is not a characteristic of UJT
    a) Saturation Current b) Negative Resistance c) Peak point Voltage d) Bilateral Conduction
    Ans : Saturation Current
    A zener diode is destroyed if it
    a) is forward biased b) is reverse biased c) carries more than the rated current d) carries less than the rated current
    Ans : carries more than the rated current
    In a full wave rectification, if the input frequency is 50 Hz, then the output has a frequency of
    a) 100 Hz b) 50 Hz c) 25 Hz d) 200 Hz
    Ans : 50 Hz
    The multivibrator which generates square wave of its own is the -------- multivibrator
    a) monostable b) astable c) bistable d) tristable
    Ans : astable
    The output impedance of a transistor is
    a) high b) low c) infinity d) zero
    Ans : zero
    Revered members, I have reproduced the questions verbatim.

    2. Relevant equations

    3. The attempt at a solution
    Last edited by a moderator: Mar 2, 2012
  2. jcsd
  3. Mar 2, 2012 #2


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    Staff Emeritus
    Science Advisor
    Homework Helper
    Education Advisor

    Re: Electronics questions -- help needed

    You need to explain your thinking behind your responses.
  4. Mar 2, 2012 #3


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    Staff: Mentor

    Re: Electronics questions -- help needed

    It's a big call to state that the output impedance of anything is zero!
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