1. A control system working under unknown random action is called
Correct : C. stochastic control system
2. The first order control system, which is is well designed, has a
Correct : C. large negative transfer function pole
3. Zero-order hold used in practical reconstruction of continuous-time signals is mathematically represented as a weighted-sum of rectangular pulses
shifted by:
Correct : B. integer multiples of the sampling interval
4. Sampling can be done by:
Correct : D. all of the mentioned
5. The first step required to convert analog signal to digital is :
Correct : A. sampling
6. Sampling is necessary :
Correct : B. where high accuracy is required
7. _______________ is a sampling pattern which is repeated periodically
Correct : B. multi order sampling
8. Aliasing is caused when:
Correct : C. sampling frequency must be less to the message signal
9. The signal is reconstructed back with the help of
Correct : C. signal is reconstructed with zero order holds and extrapolations
10. A control system working under unknown random actions is called ---
Correct : C. stochastic control system
11. Zero initial condition for a system means
Correct : D. system is at rest and no energy is stored in any of its components
12. The first order control system ,which is well designed has a
Correct : C. large negative transfer function pole
13. A zero order hold is used with sampled data system to
Correct : B. reconstruct the sampled signal
14. A controller is basically a ---
Correct : B. comparator
15. Z and Laplace transform are related by:
Correct : B. s =ln z/t
16. What is the z-transform of the signal x[n] = an
u(n)?
Correct : C. x(z) = z/z-a
17. Which one of the following rules determine the mapping of s-plane to z-plane?
Correct : D. all of the mentioned
18. Assertion (A): The z-transform of the output of the sampler is given by the series.
Reason (R): The relationship is the result of the application of z = e-sT, where T stands for the time gap between the samples.
Correct : C. a is true but r is false
19. Inverse z-transform of the system can be calculated using:
Correct : D. all of the mentioned
20. If the z transform of x(n) is X(z) =z(8z-7)/4z2
-7z+3, then the final value theorem is :
Correct : A. 1
21. Difference equation model results in:
Correct : D. both a & b
22. Which of the following is an advantage of Laplace transform method
Correct : D. both b & c
23. Analysis of control system by Laplace transform technique is not possible for
Correct : A. discrete time systems
24. Z-transform is used in:
Correct : B. discrete optimal problem
25. Unit step response of the system described by the equation y(n) +y(n-1) =x(n) is:
Correct : A. z2/(z+1)(z-1)
26. Difference equation model results in:
Correct : D. both a and b
27. For relative stability of the system which of the following is sufficient?
Correct : C. both a and b
28. Stability of a system implies that :
Correct : A. small changes in the system input does not result in large change in system output
29. Linear mathematical model applies to :
Correct : B. stable systems
30. With feedback _____ reduces.
Correct : B. system gain
31. Asymptotic stability is concerned with:
Correct : B. a system not under influence of input
32. A linear time invariant system is stable if :
Correct : C. both a and b
33. If a system is given unbounded input then the system is:
Correct : C. not defined
34. If the impulse response in absolutely integrable then the system is :
Correct : A. absolutely stable
35. If root of the characteristic equation has positive real part the system is :
Correct : B. unstable
36. The use of sampled data control system are:
Correct : C. whenever a transmission channel forms a part of closed loop
37. Jury’s test determines whether the roots of a polynomial lie:
Correct : B. within the unit circle
38. The transformation technique in which there is one to one mapping from s-domain to z-domain is
Correct : C. bilinear transformation method
39. Parallel form of realisation is done in
Correct : A. high speed filtering applications
40. In cascade form of realization, how many bits should be used to represent the FIR filter coefficients in order to avoid the quantization effect on
filter coefficients?
Correct : B. 12 to 14
41. How is the sampling rate conversion achieved by factor I/D?
Correct : D. all of above
42. In the cascaded form of realisation, the polynomials are factored into
Correct : A. product of 1st-order and 2nd-order polynomials
43. Open loop transfer function of a system having one zero with a positive real value is called.
Correct : D. non-minimum phase function
44. Consider the function F (s)= 5/s(s2+3s+2), the initial value of f(t) is:
Correct : D. 0
45. In a closed loop for which the output is the speed of the motor, the output rate control can be used to:
Correct : A. limit the speed of the motor
46. The transfer function of any stable system which has no zeros or poles in the right half of the s-plane is said to be:
Correct : A. minimum phase transfer function
47. State model representation is possible using _________
Correct : D. all of the above
48. Conventional control theory is applicable to ______ systems
Correct : A. siso
49. The transfer function for the state representation of the continuous time LTI system: dq(t)/dt=Aq(t)+Bx(t)
Y(t)=Cq(t)+Dx(t) is given by
Correct : A. c(si-a)-1b+d
50. The system which works on the initial condition without any input applied to it is called as :
Correct : A. homogeneous system
51. The transfer function of a LTI system is given as 1/(s+1). What is the steady-state value of the unit-impulse response?
Correct : A. 0
52. The values of the characteristic equation is given by:
Correct : A. eigen values
53. The state variable representation is preferred
Correct : C. to make a plant simple and to control the transient response
54. With the knowledge of state space representation the transfer function of the system
Correct : B. can be determined completely
55. Which among the following are the interconnected units of state diagram representation?
Correct : D. all of the above
56. Which among the following controls the speed of D.C. motor?
Correct : D. tachometer
57. State model representation is possible using _________
Correct : D. all of the above
58. Which among the following constitute the state model of a system in addition to state equations?
Correct : B. . output equations
59. Which among the following plays a crucial role in determining the state of dynamic system?
Correct : A. . state variables
60. What is Eigen value?
Correct : C. a scalar associated with a given linear transformation
61. Let us consider a 3×3 matrix A with Eigen values of λ1, λ2, λ3 and the Eigen values of A-1 are?
Correct : B. 1/λ1,1/λ2,1/λ3
62. The Eigen values of a 3×3 matrix are λ1, λ2, λ3 then the Eigen values of a matrix A3 are __________
Correct : C. λ31,λ32,λ33
63. State space analysis is applicable even if the initial conditions are _____
Correct : B. non-zero
64. According to the property of state transition method, e0 is equal to _____
Correct : C. e-at
65. Which mechanism in control engineering implies an ability to measure the state by taking measurements at output?
Correct : B. observability
66. State model representation is possible using _________
Correct : D. all of the mentioned
67. Which among the following constitute the state model of a system in addition to state equations?
Correct : B. output equations
68. Which among the following are the interconnected units of state diagram representation?
Correct : D. all of the mentioned
69. Which among the following is a unique model of a system?
Correct : A. transfer function
70. State model is generally not suitable for measuring:
Correct : D. both a and b
71. ______________ are the techniques for converting general state models into canonical one.
Correct : C. diagoanlization
72. The diagonalizing matrix is also known as:
Correct : B. modal matrix
73. 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
74. 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
75. Kalman’s test is for :
Correct : D. observability and controllability
76. Consider a system if represented by state space equation and x1 (t) =x2 (t), then the system is:
Correct : B. uncontrollable
77. 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
78. The impulse response of a linear LTI system is given as g (t) = e(-t)The transfer function of the system is equal to:
Correct : C. 1/(s+1)
79. An oberser or program that that estimates less than n state variables, where n is dimension of stage vector is called
Correct : A. reduced order state observer
80. Gilbert's test is used to check
Correct : D. controlability & observability
81. The necessary and sufficient condition for the system to be completely state controllable is that therank of the composite matrix QC is