

MCQOPTIONS
Saved Bookmarks
This section includes 86 Mcqs, each offering curated multiple-choice questions to sharpen your Electrical Engineering knowledge and support exam preparation. Choose a topic below to get started.
51. |
Jury’s test determines whether the roots of a polynomial lie: |
A. | close to unit circle |
B. | within the unit circle |
C. | outside the unit circle |
D. | on the unit circle |
Answer» C. outside the unit circle | |
52. |
The use of sampled data control system are: |
A. | for using analog components as the part of the control loop |
B. | for time division of control components |
C. | whenever a transmission channel forms a part of closed loop |
D. | none of the mentioned |
Answer» D. none of the mentioned | |
53. |
If root of the characteristic equation has positive real part the system is : |
A. | stable |
B. | unstable |
C. | marginally stable |
D. | linear |
Answer» C. marginally stable | |
54. |
If the impulse response in absolutely integrable then the system is : |
A. | absolutely stable |
B. | unstable |
C. | linear |
D. | stable |
Answer» B. unstable | |
55. |
A linear time invariant system is stable if : |
A. | system in excited by the bounded input, the output is also bounded |
B. | in the absence of input output tends zero |
C. | both a and b |
D. | system in excited by the bounded input, the output is not bounded |
Answer» D. system in excited by the bounded input, the output is not bounded | |
56. |
If a system is given unbounded input then the system is: |
A. | stable |
B. | unstable |
C. | not defined |
D. | linear |
Answer» D. linear | |
57. |
With feedback _____ reduces. |
A. | system stability |
B. | system gain |
C. | system stability and gain |
D. | damping |
Answer» C. system stability and gain | |
58. |
Asymptotic stability is concerned with: |
A. | a system under influence of input |
B. | a system not under influence of input |
C. | a system under influence of output |
D. | a system not under influence of ou |
Answer» C. a system under influence of output | |
59. |
Stability of a system implies that : |
A. | small changes in the system input does not result in large change in system output |
B. | small changes in the system parameters does not result in large change in system output |
C. | small changes in the initial conditions does not result in large change in system output |
D. | small changes in the initial conditions result in large change in system output |
Answer» B. small changes in the system parameters does not result in large change in system output | |
60. |
Linear mathematical model applies to : |
A. | linear systems |
B. | stable systems |
C. | unstable systems |
D. | all of the mentioned |
Answer» C. unstable systems | |
61. |
Unit step response of the system described by the equation y(n) +y(n-1) =x(n) is: |
A. | z2/(z+1)(z-1) |
B. | z/(z+1)(z-1) |
C. | z+1/z-1 |
D. | z(z-1)/z+1 |
Answer» B. z/(z+1)(z-1) | |
62. |
For relative stability of the system which of the following is sufficient? |
A. | gain margin |
B. | phase margin |
C. | both a and b |
D. | magnitude |
Answer» D. magnitude | |
63. |
Z-transform is used in: |
A. | continuous optimal control problem |
B. | discrete optimal problem |
C. | control systems |
D. | none of the mentione |
Answer» C. control systems | |
64. |
Which of the following is an advantage of Laplace transform method |
A. | it gives solution in frequency domain only |
B. | it gives total solution more systematically |
C. | initial conditions are incorporated in the very first step |
D. | both b & c |
Answer» E. | |
65. |
Difference equation model results in: |
A. | sampled-data systems |
B. | numerical analysis of continuous time systems |
C. | continuous time feedback systems |
D. | both a & b |
Answer» E. | |
66. |
If the z transform of x(n) is X(z) =z(8z-7)/4z2 -7z+3, then the final value theorem is : |
A. | 1 |
B. | 2 |
C. | ∞ |
Answer» B. 2 | |
67. |
Analysis of control system by Laplace transform technique is not possible for |
A. | discrete time systems |
B. | linear systems |
C. | time invarient systems |
D. | unstable continuous time systems |
Answer» B. linear systems | |
68. |
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. |
A. | both a and r are true and r is correct explanation of a |
B. | both a and r are true but r is not correct explanation of a |
C. | a is true but r is false |
D. | a is false but r is true |
Answer» D. a is false but r is true | |
69. |
Inverse z-transform of the system can be calculated using: |
A. | partial fraction method |
B. | long division method |
C. | basic formula of the z-transform |
D. | all of the mentioned |
Answer» E. | |
70. |
Which one of the following rules determine the mapping of s-plane to z-plane? |
A. | right side of the s-plane maps into outside of the unit circle in z-plane |
B. | left half of s-plane maps into inside of the unit circle |
C. | imaginary axis in s-plane maps into the circumference of the unit circle |
D. | all of the mentioned |
Answer» E. | |
71. |
What is the z-transform of the signal x[n] = an u(n)? |
A. | x(z) =1/z-1 |
B. | x(z) = 1/1-z |
C. | x(z) = z/z-a |
D. | x(z) = 1/z-a |
Answer» D. x(z) = 1/z-a | |
72. |
Z and Laplace transform are related by: |
A. | s = ln z |
B. | s =ln z/t |
C. | s =z |
D. | s= t/ln z |
Answer» C. s =z | |
73. |
A controller is basically a --- |
A. | sensor |
B. | comparator |
C. | amplifier |
D. | clipper |
Answer» C. amplifier | |
74. |
A zero order hold is used with sampled data system to |
A. | make it critically damped |
B. | reconstruct the sampled signal |
C. | improve the stability of the system |
D. | convert it to a continuous system |
Answer» C. improve the stability of the system | |
75. |
The first order control system ,which is well designed has a |
A. | small bandwidth |
B. | negative time constant |
C. | large negative transfer function pole |
D. | none of the above |
Answer» D. none of the above | |
76. |
Zero initial condition for a system means |
A. | input reference signal is zero |
B. | zero stored energy |
C. | no initial movement of moving parts |
D. | system is at rest and no energy is stored in any of its components |
Answer» E. | |
77. |
A control system working under unknown random actions is called --- |
A. | computer control system |
B. | digital data system |
C. | stochastic control system |
D. | adaptive control system |
Answer» D. adaptive control system | |
78. |
The signal is reconstructed back with the help of |
A. | zero order hold circuits |
B. | extrapolations |
C. | signal is reconstructed with zero order holds and extrapolations |
D. | signal is not reconstructed |
Answer» D. signal is not reconstructed | |
79. |
_______________ is a sampling pattern which is repeated periodically |
A. | single order sampling |
B. | multi order sampling |
C. | zero order sampling |
D. | unordered sampling |
Answer» C. zero order sampling | |
80. |
Sampling is necessary : |
A. | in complex control systems |
B. | where high accuracy is required |
C. | non automated control systems |
D. | automated control system |
Answer» C. non automated control systems | |
81. |
Aliasing is caused when: |
A. | sampling frequency must be equal to the message signal |
B. | sampling frequency must be greater to the message signal |
C. | sampling frequency must be less to the message signal |
D. | sampling frequency must be greater than or equal to the message signal |
Answer» D. sampling frequency must be greater than or equal to the message signal | |
82. |
The first step required to convert analog signal to digital is : |
A. | sampling |
B. | holding |
C. | reconstruction |
D. | quantization |
Answer» B. holding | |
83. |
Sampling can be done by: |
A. | impulse train sampling |
B. | natural sampling |
C. | flat-top sampling |
D. | all of the mentioned |
Answer» E. | |
84. |
Zero-order hold used in practical reconstruction of continuous-time signals is mathematically represented as a weighted-sum of rectangular pulses shifted by: |
A. | any multiples of the sampling interval |
B. | integer multiples of the sampling interval |
C. | one sampling interval |
D. | 1 second intervals |
Answer» C. one sampling interval | |
85. |
The first order control system, which is is well designed, has a |
A. | small bandwidth |
B. | negative time constant |
C. | large negative transfer function pole |
D. | none of the above |
Answer» D. none of the above | |
86. |
A control system working under unknown random action is called |
A. | computer control system |
B. | digital data system |
C. | stochastic control system |
D. | adaptive control system |
Answer» D. adaptive control system | |