Quiznetik

Control System Engineering (CSE) | Set 2

1. The constant M-circle represented by the equation x^2+2.25x+y^2=-1.25 has the value of M equal to:

Correct : C. 3

2. What is the value of M for the constant M circle represented by the equation 8x2+18x+8y2+9=0?

Correct : C. 3

3. The constant N loci represented by the equation x^2+x+y^2=0 is for the value of phase angle equal to:

Correct : D. 90°

4. 4 DESIGN OF COMPENSATORS USING BODE PLOT

Correct : A. -1 and origin

5. Which one of the following statements is correct? Nichol’s chart is useful for the detailed study analysis of:

Correct : A. closed loop frequency response

6. Frequency range of bode magnitude and phases are decided by :

Correct : D. none of the above

7. OLTF contains one zero in right half of s- plane then

Correct : C. close loop system is unstable for higher gain

8. The critical value of gain for a system is 40 and gain margin is 6dB. The system is operating at a gain of:

Correct : A. 20

9. Nichol’s chart is useful for the detailed study and analysis of:

Correct : A. closed loop frequency response

10. The roots of the characteristic equation of the second order system in which real and imaginary part represents the :

Correct : B. damping and damped frequency

11. An all-pass network imparts only

Correct : D. 180 degree phase shift to the input

12. Which of the following is an effect of lag compensation?

Correct : A. decrease bandwidth

13. PD controller:

Correct : B. rise time decreases

14. PID controller:

Correct : A. decreases steady state error and improves stability

15. PI controller:

Correct : C. transient response becomes poorer

16. Proportional controller

Correct : D. increases steady state error

17. Lead compensator increases bandwidth

Correct : A. true

18. Lag compensator reduces

Correct : B. velocity constant

19. A linear time invariant system is stable if :

Correct : C. both a and b

20. Asymptotic stability is concerned with:

Correct : B. a system not under influence of input

21. Bounded input and Bounded output stability notion concerns with :

Correct : A. a system under influence of input

22. If a system is given unbounded input then the system is:

Correct : C. not defined

23. Linear mathematical model applies to :

Correct : B. stable systems

24. For non-linear systems stability cannot be determined due to:

Correct : D. all of the mentioned

25. If the impulse response in absolutely integrable then the system is :

Correct : A. absolutely stable

26. The roots of the transfer function do not have any effect on the stability of the system.

Correct : B. false

27. Roots with higher multiplicity on the imaginary axis makes the system :

Correct : B. unstable

28. Roots on the imaginary axis makes the system :

Correct : C. marginally stable

29. If root of the characteristic equation has positive real part the system is :

Correct : B. unstable

30. A linear system can be classified as :

Correct : D. all of the mentioned

31. is a quantitative measure of how fast the transients die out in the system.

Correct : D. relative stability

32. Root locus of s(s+2)+K(s+4) =0 is a circle. What are the coordinates of the center of this circle?

Correct : C. -4,0

33. The main objective of drawing root locus plot is :

Correct : D. both b and c

34. While increasing the value of gain K, the system becomes

Correct : A. less stable

35. The addition of open loop poles pulls the root locus towards:

Correct : D. the right and system becomes unstable

36. Root locus is used to calculate:

Correct : D. relative stability

37. Routh Hurwitz criterion is better than root locus.

Correct : B. false

38. Consider the following statements regarding root loci:

Correct : B. all root loci end at the respective zeros of g(s) h(s) or go to infinity

39. Number of roots of characteristic equation is equal to the number of

Correct : A. branches

40. Which of the following statements are correct?

Correct : C. root locus is for the negative feedback and complementary root locus is for the positive feedback systems

41. Consider the loop transfer function K(s+6)/(s+3)(s+5) In the root locus diagram the centroid will be located at:

Correct : C. -2

42. Which one of the following applications software’s is used to obtain an accurate root locus for?

Correct : B. matlab

43. Which one of the following is not the property of root loci?

Correct : A. the root locus is symmetrical about imaginary axis

44. The breakaway point calculated mathematically must always lie on the root locus.

Correct : A. true

45. What is the number of the root locus segments which do not terminate on zeroes?

Correct : C. the difference between the number of poles and zeroes

46. Which one of the following are correct? The root locus is the path of the roots of the characteristic equation traced out in the s- plane?

Correct : C. as a system parameter is changed

47. If the gain of the system is reduced to a zero value, the roots of the system in the s- plane,

Correct : D. coincide with the poles

48. The addition of open loop zero pulls the root loci towards:

Correct : A. the left and therefore system becomes more stable

49. If root loci plots of a particular control system do not intersect the imaginary axis at any point, then the gain margin of the system will be:

Correct : D. infinite

50. When the number of poles is equal to the number of zeroes, how many branches of root locus tends towards infinity?

Correct : C. 0

51. System transformation on function H(z) for a discrete time LTI system expressed in state variable form with zero initial condition

Correct : A. -1b+d

52. State space analysis is applicable for non- linear systems and for multiple input and output systems.

Correct : A. true

53. When human being tries to approach an object, his brain acts as,

Correct : B. a controller

54. For two-phase AC servomotor, if the rotor’s resistance and reactance are respectively R and X, its length and diameter are respectively L and D then,

Correct : C. x/r is small but l/d is large

55. Error detector:

Correct : A. armature controlled fhp dc motor

56. Servomotor:

Correct : B. a pair of synchronous transmitter and control transformer

57. Amplifier:

Correct : D. amplidyne

58. A differentiator is usually not a part of a control system because it

Correct : C. increases input noise

59. If the gain of the critical damped system is increased it will behave as

Correct : D. underdamped

60. In a control system integral error compensation                steady state error

Correct : B. minimizes

61. With feedback            reduces.

Correct : B. system gain

62. An amplidyne can give which of the following characteristics?

Correct : D. constant current, constant voltage and constant power

63. Which of the following can be measured by LVDT?

Correct : D. all of the mentioned

64. directly converts temperature into voltage.

Correct : A. thermocouple

65. The transfer function technique is considered as inadequate under which of the following conditions?

Correct : D. all of the mentioned

66. Which of the following is the output of a thermocouple?

Correct : D. d.c. voltage

67. A system is said to be                           if it is possible to transfer the system state from any initial state to any desired state in finite interval of time.

Correct : A. controllable

68. A system is said to be                                    if every state can be completely identified by measurements of the outputs at the finite time interval.

Correct : B. observable

69. Kalman’s test is for :

Correct : D. observability and controllability

70. Consider a system if represented by state space equation and x1 (t) =x2 (t), then the system is:

Correct : B. uncontrollable

71. A transfer function of the system does not have pole-zero cancellation? Which of the following statements is true?

Correct : B. system is completely controllable and observable

72. Complex conjugate pair:

Correct : B. focus point

73. Pure imaginary pair:

Correct : A. centre

74. Real and equal but with opposite sign.

Correct : C. saddle point

75. Real distinct and negative.

Correct : D. stable node

76. Stability of a system implies that :

Correct : D. all of the above mentioned

77. If the roots of the have negative real parts then the response is

Correct : D. bounded

78. Which among the following is a unique model of a system?

Correct : A. transfer function

79. According to the property of state transition method, e0 is equal to

Correct : C. e-at

80. Which mechanism in control engineering implies an ability to measure the state by taking measurements at output?

Correct : B. observability

81. State model representation is possible using

Correct : D. all of the mentioned

82. Which among the following constitute the state model of a system in addition to state equations?

Correct : B. output equations

83. Which among the following plays a crucial role in determining the state of dynamic system?

Correct : A. state variables

84. Which among the following are the interconnected units of state diagram representation?

Correct : D. all of the mentioned

85. State space analysis is applicable even if the initial conditions are

Correct : B. non-zero

86. Conventional control theory is applicable to              systems

Correct : A. siso

87. Insertion of negative feedback in control system affects:

Correct : B. the transient response to decay very fast