Control Systems – Multiple Choice Questions (MCQs)

1. 61. The effect of negative feedback on bandwidth is:

   • A. Increases bandwidth
   • B. Decreases bandwidth
   • C. No effect on bandwidth
   • D. Makes bandwidth infinite

2. 62. The steady-state error of a system is primarily a function of the:

   • A. Type of the system and type of input
   • B. Gain of the system
   • C. Natural frequency
   • D. Damping ratio

3. 63. The term "disturbance rejection" in control systems refers to the ability of the system to:

   • A. Track input signals
   • B. Maintain desired output despite external disturbances
   • C. Achieve fast response
   • D. Reduce steady-state error

4. 64. Which element in a control system provides the feedback signal?

   • A. Controller
   • B. Actuator
   • C. Sensor
   • D. Reference input

5. 65. The state transition matrix for a linear time-invariant system is given by:

   • A. e^At
   • B. e^-At
   • C. A^-1
   • D. I

6. 66. What is the minimum number of states required to describe an nth-order system?

   • A. n
   • B. n-1
   • C. n+1
   • D. 2n

7. 67. The gain crossover frequency is generally associated with:

   • A. Steady-state performance
   • B. Transient response
   • C. Stability margins
   • D. Noise rejection

8. 68. The phase crossover frequency is generally associated with:

   • A. Steady-state performance
   • B. Transient response
   • C. Stability margins
   • D. Noise rejection

9. 69. The initial slope of the magnitude plot in a Bode diagram for a type 1 system is:

   • A. 0 dB/decade
   • B. -20 dB/decade
   • C. -40 dB/decade
   • D. -60 dB/decade

10. 70. The final slope of the magnitude plot in a Bode diagram depends on the:

    • A. Number of poles
    • B. Number of zeros
    • C. Difference between poles and zeros
    • D. System type

11. 71. What is the characteristic equation of a closed-loop system with open-loop transfer function G(s) and feedback H(s)?

    • A. 1 + G(s)H(s) = 0
    • B. 1 - G(s)H(s) = 0
    • C. G(s)H(s) = 0
    • D. G(s) + H(s) = 0

12. 72. The transient response of a control system refers to its behavior:

    • A. After a long time
    • B. During the initial period after an input change
    • C. At steady-state
    • D. Due to noise