Home / ECE / Signals and Systems :: Section 6

ECE :: Signals and Systems

  1. The triangular wave of the given figure can be written as v(t) = u(t) - tu(t) + (t - 1) u(t - 1)

  2. A.
    True
    B.
    False

  3. The function A est where s = s + jω represents

  4. A.
    A phasor whose magnitude changes with time
    B.
    A phasor whose frequency is ω
    C.
    A phasor rotating in counterclockwise direction at angular frequency ω and whose magnitude increases with t
    D.
    A phasor rotating in clockwise direction at angular frequency ω and whose magnitude increases with t

  5. Half wave sysmmetry means f(t) = - f(t ± T/2).

  6. A.
    True
    B.
    False

  7. When a complex voltage wave is applied to a capacitor the resulting current wave is more distorted than the voltage wave.

  8. A.
    True
    B.
    False

  9. If for k ≥ 0 and xk = 0 for k < 0, z transform of the sequence x is


  10. Fourier transform of non periodic DT signal is

  11. A.
    aperiodic
    B.
    Periodic
    C.
    both a and b
    D.
    None of these

  12. The Fourier transform of f(t) = cos ω0t is

  13. A.
    p[δω0 + δ(- ω0)]
    B.
    p[δ(ω - ω0) + δ(ω + ω0)]
    C.
    p[δω0 - δ(- ω0)]
    D.
    p[δ(ω - ω0) - δ(ω + ω0)]

  14. The function shown in the figure

  15. A.
    impulse function
    B.
    signum function
    C.
    unit step function
    D.
    none of the above

  16. Assertion (A):

    Reason (R): An impulse has a very high magnitude but very short duration.

  17. 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 true, R is false
    D.
    A is false, R is true

  18. Energy spectral density is equal to for a signal g(t)

  19. A.
    |G(f)|2
    B.
    |g(t)|2
    C.
    |G(f)|2/Bandwidth
    D.