Automatic Control System MCQ-3

1. When the ouput of the system is independent of input signal, then the system is

(A) Open loop control system
(B) Closed loop control system
(C) Both (a) and (b)
(D) None of these

2. A closed loop system basically different from open control system due to ______

(A) Error signal
(B) Actuating signal
(C) Servomechanism
(D) Feed back

3. Introduction of feedback reduces the effect of

(A) Error signal
(B) Disturbances
(C) Noise signal
(D) All of the above

4. Which of the following is an example of the open loop control system ?

(A) Field controlled DC motor
(B) Metadyne
(C) Stroboscope
(D) Ward Veonard control

5. The output is feedback at the input side through the ______ point.

(A) Differential
(B) Summing
(C) Take off
(D) None of these

6. Advantages of open loop system is/are :

(A) Simple and economical
(B) Accurate
(C) Reliable
(D) All of the above

7. The Laplace transform df(t)/dt of is :

(A) SF(s)+f(0)
(B) SF(s)-f(0)
(C) F(s)/s
(D) F(s)

8. The inverse Laplace of 1/S² is :

(A) t²
(B) t
(C) 1
(D) 0

9. The transfer function of a system is defined as the ratio of output to input in ______

(A) Laplace Transform
(B) Forier Transform
(C) Z-Transform
(D) None of these

10. Three blocks with gains of 5,8 and 2 respectively are connected in series, The total gain of the arrangement is :

(A) 15
(B) 80
(C) 40
(D) 20

11. Tachometers is a device which converts :

(A) Electrical energy to machanical energy
(B) Mechanical energy to electrical energy
(C) Both (a) and (b)
(D) None of these

12. If the damping ratin is equal to 1, a second-order system is ______

(A) Having maginary roots of the characteristic equation
(B) Underdamped
(C) Critically damped with unequal roots
(D) Critically damped with equal roots

13. Root locus is symmetrical about :

(A) Real axis
(B) Imaginary axis
(C) Both real and imaginary axis
(D) None of these

14. A signal which value changes from zero to another level ‘N’ in negligible rime is called ______

(A) Ramp signal
(B) Impulse signal
(C) Step signal
(D) None of these

15. In time response specification, The time require to rach 50% off the final value in first attempt is called

(A) Settling time
(B) Delay time
(C) Rise time
(D) Peak time

16. If the system has multiple poles on the imaginary axis, the system is :

(A) Unstable
(B) Stable
(C) Conditionally stable
(D) Marginally stable

17. A graph of the magnitude of gain versus frequency is called ______

(A) Break frequency plot
(B) Frequency response plot
(C) Frequency stability plot
(D) Transient response plot

18. Which of the following will constiture the state model of the system ?

(A) State equations
(B) Output equations
(C) Both (a) and (b)
(D) None of these

19. The Nyquist plot intersect the real axis at a=-2, the gain margin is

(A) 2
(B) -2
(C) 1/2
(D) None of these

20. Two stator windings of AC servomoter are oriented how many electrical degree a part

(A) 60°
(B) 90°
(C) 120°
(D) 180°