1. QUIZ
Note: Attempt all 15 multiple-choice questions (MCQs). Each question carries one mark.
1. Question: What is the purpose of a controller in a control system?
- A) To sense the output
- B) To amplify the input
- C) To regulate the system output
- D) To generate disturbances
2. Question: In a feedback control system, what does the term 'open-loop gain' refer to?
- A) The gain without feedback
- B) The gain with infinite feedback
- C) The gain with unity feedback
- D) The gain with proportional feedback
3. Question: What is the transfer function of an integrator in Laplace domain?
- A) 1/s
- B) s
- C) 1
- D) s^2
4. Question: Which stability criterion is used to determine the stability of a system by examining the
location of poles in the s-plane?
- A) Bode stability criterion
- B) Nyquist stability criterion
- C) Routh-Hurwitz stability criterion
- D) Root locus stability criterion
5. Question: The settling time of a control system is the time required for the system output to reach:
- A) 90% of the final value
- B) 63.2% of the final value
- C) 50% of the final value
- D) 10% of the final value
6. Question: What is the primary purpose of a lead compensator in control system design?
- A) To increase system bandwidth
- B) To reduce steady-state error
- C) To improve transient response
- D) To decrease system gain
7. Question: Which of the following represents a type-0 system?
- A) Integral controller
- B) Proportional controller
- C) Derivative controller
- D) Proportional-Integral (PI) controller
8. Question: The concept of 'damping ratio' in a second-order system is related to:
- A) The rate of decay of oscillations
- B) The amplitude of oscillations
- C) The frequency of oscillations
- D) The phase shift of oscillations
2. 9. Question: In the frequency domain, what does the phase margin indicate about a system's
stability?
- A) Margin of safety before instability
- B) Rate of convergence to stability
- C) Oscillation frequency of the system
- D) Rate of divergence to instability
10. Question: What is the primary function of a compensator in control system design?
- A) To stabilize an unstable system
- B) To reduce the system order
- C) To add complexity to the system
- D) To amplify the input signal
11. Question: The Laplace transform of a unit step function is:
- A) 1/s
- B) s
- C) 1
- D) e^(-s)
12. Question: What is the effect of a derivative controller on the steady-state error of a system?
- A) It reduces the steady-state error
- B) It increases the steady-state error
- C) It has no effect on the steady-state error
- D) It makes the system unstable
13. Question: Which of the following is a disadvantage of using a P-controller alone?
- A) High sensitivity to noise
- B) Low steady-state error
- C) Improved transient response
- D) Better disturbance rejection
14. Question: What is the main purpose of the root locus method in control system analysis?
- A) To determine the frequency response
- B) To analyse transient response
- C) To investigate closed-loop pole movements
- D) To calculate the steady-state error
15. Question: What does the term 'gain margin' represent in the frequency domain analysis of a
control system?
- A) The range of gain for stability
- B) The rate of change of gain
- C) The difference between maximum and minimum gain
- D) The stability of the system at zero gain
3. QUIZ (ANSWER-KEY)
(WINTER TERM CLASSES-717/B4)
The correct answers for each of the questions:
1. C) To regulate the system output
2. A) The gain without feedback
3. A) 1/s
4. C) Routh-Hurwitz stability criterion
5. B) 63.2% of the final value
6. A) To increase system bandwidth
7. B) Proportional controller
8. A) The rate of decay of oscillations
9. A) Margin of safety before instability
10. A) To stabilize an unstable system
11. A) 1/s
12. C) It has no effect on the steady-state error
13. A) High sensitivity to noise
14. C) To investigate closed-loop pole movements
15. A) The range of gain for stability
