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  1. Compared to a p-n junction with NA = ND = 1014/cm3, which one of the following statements is TRUE for a p-n junction with NA = ND = 1020/cm3?

  2. A.
    Reverse breakdown voltage is lower and depletion capacitance is lower
    B.
    Reverse breakdown voltage is higher and depletion capacitance is lower
    C.
    Reverse breakdown voltage is lower and depletion capacitance is higher
    D.
    Reverse breakdown voltage is higher and depletion capacitance is higher

  3. Which of the following are universal gates?

    1. NAND
    2. NOR
    3. XOR
    Select the correct answer from the codes given below:

  4. A.
    1 and 2 only
    B.
    1 and 3 only
    C.
    2 and 3 only
    D.
    1, 2 and 3

  5. Consider the following statements:
    To draw a.c. equivalent circuit of a transistors, all

    1. d.c. sources are shorted
    2. a.c. sources are shorted
    3. d.c. sources are opened
    4. a.c. sources are connected to d.c. sources
    Which of the above statements is/are correct?

  6. A.
    2 and 4
    B.
    1 and 2
    C.
    1 only
    D.
    3 and 4

  7. How many number of branches the root loci of the equation s(s + 2)(s + 3) + K(s + 2) = 0 have?

  8. A.
    Zero
    B.
    One
    C.
    Two
    D.
    Three

  9. For the circuit of the following figure, with an ideal op-amp, the maximum phase shift of the output with reference to the input is :

  10. A.
    B.
    90°
    C.
    -90°
    D.
    ± 180°

  11. Consider the function where F(s) is the Laplace transform of f(t). What is the steady-state value of f(t)?

  12. A.
    Zero
    B.
    One
    C.
    Two
    D.
    A value between - 1 and + 1

  13. The Nyquist plot of a stable, transfer function G(s) is shown in the figure. We are interested in the stability of the closed loop system in the feedback configuration shown.

    Which of the following statements is true?

  14. A.
    G(s) is an all-pass filter
    B.
    G(s) has a zero in the right-half plane
    C.
    G(s) is the impedance of a passive network
    D.
    G(s) is marginally stable

  15. The output y(t) of a continuous-time system S for the input x(t) is given by:

    Which of the following is incorrect?

  16. A.
    S is linear and time-invariant
    B.
    S is linear and time-varying
    C.
    S is non-linear and time-invariant
    D.
    S is non-linear and time-varying

  17. Consider the following statements regarding the properties of an R-L-C series circuit under resonance:

    1. Current in the circuit is in phase with applied voltage
    2. Voltage drop across capacitor C and inductance L are equal in magnitude.
    3. Voltage across the capacitor is equal in magnitude to the applied voltage.
    4. Current in the circuit is maximum.
    Which of the above statements is/are correct?

  18. A.
    1 only
    B.
    1, 2 and 4
    C.
    2 and 4
    D.
    1, 3 and 4

  19. Which of the following devices is used at the first stage of an electronic voltmeter?

  20. A.
    BJT
    B.
    SCR
    C.
    MOSFET
    D.
    UJT