Bode Plot MCQ

1. A system has 14 poles and 2 zeros in its open-loop transfer function. The slope of its highest frequency asymptote in its magnitude plot is

  1. -40 dB/dec
  2. -240 dB/dec
  3. +40 dB/dec
  4. +240 dB/dec

Answer
Answer. b

2. For a type-I system, the intersection of the initial slope of the bode plot with 0 dB axis gives

  1. steady-state error
  2. error constant
  3. phase margin
  4. cross-over frequency

Answer
Answer. b

3. Gain margin is the factor by which the system gain can be increased to drive it to

  1. critically damped state
  2. the verge of instability
  3. oscillation
  4. stability

Answer
Answer. b

4. In the bode plot of a unity feedback control system, the value of phase of G(jω) at the gain cross-over frequency is -125°. The phase margin of the system is

  1. 125°
  2. -55°
  3. 55°
  4. 125°

Answer
Answer. c

5. What will be the gain margin in dB of a system having the following open-loop transfer function?

$G(s)H(s)=\frac{2}{s(s+1)}$

  1. 0.5
  2. 2
  3. 0

Answer
Answer. a