Home / GATE 2017-2018 / GATE ECE :: Practice Test Paper 1

GATE 2017-2018 :: GATE ECE

  1. With initial condition x(1) = 0.5 , the solution of the differential equation, t dx/dt + x = t is
  2. A.
    x = t - 1/2
    B.
    x = t2 - 1/2
    C.
    x = t2/2
    D.
    x = t/2

  3. The diodes and capacitors in the circuit shown are ideal. The voltage v(t) across the diode D1 is

  4. A.
    cos(wt) - 1
    B.
    sin(wt)
    C.
    1 - cos(wt)
    D.
    1 - sin(wt)

  5. A source alphabet consists of N symbols with the probability of the first two symbols being the same. A source encoder increases the probability of the first symbol by a small amount ε and decreases that of the second by ε . After encoding, the entropy of the source
  6. A.
    increases
    B.
    remains the same
    C.
    increases only if N = 2
    D.
    decreases

  7. The radiation pattern of an antenna in spherical co-ordinates is given by
    F(θ) = cos4 θ; 0 ≤ θ ≤ π /2
    The directivity of the antenna is
  8. A.
    10 dB
    B.
    12.6 dB
    C.
    11.5 dB
    D.
    18 dB

  9. If x[n] = (1/3)|n| - (1/ 2)n u[n], then the region of convergence (ROC) of its Z-transform in the Z-plane will be
  10. A.
    1/3 < |z| < 3
    B.
    1/3 < |z| < 1/2
    C.
    1/2 < |z| < 3
    D.
    1/3 < |z|

  11. In the sum of products function f (X, Y, Z) = Σ(2, 3, 4, 5) , the prime implicants are
  12. A.
    .

    B.
    .

    C.
    .

    D.
    .


  13. A system with transfer function
    G(s) = [(s2 + 9)(s + 2)] / [(s + 1)(s + 3)(s + 4)]
    is excited by sin(w t) . The steady-state output of the system is zero at
  14. A.
    w = 1 rad/s
    B.
    w = 2 rad/s
    C.
    w = 3 rad/s
    D.
    w = 4 rad/s

  15. The impedance looking into nodes 1 and 2 in the given circuit is

  16. A.
    50 Ω
    B.
    100 Ω
    C.
    5 kΩ
    D.
    10.1 kΩ

  17. In the circuit shown below, the current through the inductor is

  18. A.
    2/(1 + j) A
    B.
    -1/(1 + j) A
    C.
    1/(1 + j) A
    D.
    0 A

  19. Given f(z) = 1/(z + 1) - 2/(z + 3). If C is a counterclockwise path in the z-plane such that |z + 1| = 1 the value of  is
  20. A.
    -2
    B.
    -1
    C.
    1
    D.
    2