McqMate

74

72.6k

These multiple-choice questions (MCQs) are designed to enhance your knowledge and understanding in the following areas: Electrical Engineering , Electronics and Telecommunication Engineering [ENTC] .

1. |
## 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» C. stochastic control system |

2. |
## 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» 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: |

A. | any multiples of the sampling interval |

B. | integer multiples of the sampling interval |

C. | one sampling interval |

D. | 1 second intervals |

Answer» B. integer multiples of the sampling interval |

4. |
## Sampling can be done by: |

A. | impulse train sampling |

B. | natural sampling |

C. | flat-top sampling |

D. | all of the mentioned |

Answer» D. all of the mentioned |

5. |
## The first step required to convert analog signal to digital is : |

A. | sampling |

B. | holding |

C. | reconstruction |

D. | quantization |

Answer» A. sampling |

6. |
## Sampling is necessary : |

A. | in complex control systems |

B. | where high accuracy is required |

C. | non automated control systems |

D. | automated control system |

Answer» B. where high accuracy is required |

7. |
## _______________ is a sampling pattern which is repeated periodically |

A. | single order sampling |

B. | multi order sampling |

C. | zero order sampling |

D. | unordered sampling |

Answer» B. multi order sampling |

8. |
## 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» C. sampling frequency must be less to the message signal |

9. |
## 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» C. signal is reconstructed with zero order holds and extrapolations |

10. |
## 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» C. stochastic control system |

11. |
## 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» 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 |

A. | small bandwidth |

B. | negative time constant |

C. | large negative transfer function pole |

D. | none of the above |

Answer» C. large negative transfer function pole |

13. |
## 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» B. reconstruct the sampled signal |

14. |
## A controller is basically a --- |

A. | sensor |

B. | comparator |

C. | amplifier |

D. | clipper |

Answer» B. comparator |

15. |
## 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» B. s =ln z/t |

16. |
## 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» C. x(z) = z/z-a |

17. |
## 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» 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. |

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» C. a is true but r is false |

19. |
## 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» 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 : |

A. | 1 |

B. | 2 |

C. | ∞ |

D. | 0 |

Answer» A. 1 |

21. |
## 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» D. both a & b |

22. |
## 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» D. both b & c |

23. |
## 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» A. discrete time systems |

24. |
## Z-transform is used in: |

A. | continuous optimal control problem |

B. | discrete optimal problem |

C. | control systems |

D. | none of the mentione |

Answer» B. discrete optimal problem |

25. |
## 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» A. z2/(z+1)(z-1) |

26. |
## Difference equation model results in: |

A. | sampled-data systems |

B. | numerical analysis of continuous time systems |

C. | continuous time feedback systems |

D. | both a and b |

Answer» D. both a and b |

27. |
## 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» C. both a and b |

28. |
## 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» A. small changes in the system input does not result in large change in system output |

29. |
## Linear mathematical model applies to : |

A. | linear systems |

B. | stable systems |

C. | unstable systems |

D. | all of the mentioned |

Answer» B. stable systems |

30. |
## With feedback _____ reduces. |

A. | system stability |

B. | system gain |

C. | system stability and gain |

D. | damping |

Answer» B. system gain |

31. |
## 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» B. a system not under influence of input |

32. |
## 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» C. both a and b |

33. |
## If a system is given unbounded input then the system is: |

A. | stable |

B. | unstable |

C. | not defined |

D. | linear |

Answer» C. not defined |

34. |
## If the impulse response in absolutely integrable then the system is : |

A. | absolutely stable |

B. | unstable |

C. | linear |

D. | stable |

Answer» A. absolutely stable |

35. |
## If root of the characteristic equation has positive real part the system is : |

A. | stable |

B. | unstable |

C. | marginally stable |

D. | linear |

Answer» B. unstable |

36. |
## 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» C. whenever a transmission channel forms a part of closed loop |

37. |
## 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» B. within the unit circle |

38. |
## The transformation technique in which there is one to one mapping from s-domain to z-domain is |

A. | approximation of derivatives |

B. | impulse invariance method |

C. | bilinear transformation method |

D. | backward difference for the derivative |

Answer» C. bilinear transformation method |

39. |
## Parallel form of realisation is done in |

A. | high speed filtering applications |

B. | low speed filtering applications |

C. | both a and b |

D. | none of the above |

Answer» 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? |

A. | 5 to 10 |

B. | 12 to 14 |

C. | 20 to 24 |

D. | 28 to 40 |

Answer» B. 12 to 14 |

41. |
## How is the sampling rate conversion achieved by factor I/D? |

A. | by increase in the sampling rate with (i) |

B. | by filtering the sequence to remove unwanted images of spectra of original signal |

C. | by decimation of filtered signal with factor d |

D. | all of above |

Answer» D. all of above |

42. |
## In the cascaded form of realisation, the polynomials are factored into |

A. | product of 1st-order and 2nd-order polynomials |

B. | product of 2nd-order and 3rd-order polynomials |

C. | sum of 1st-order and 2nd-order polynomials |

D. | sum of 2nd-order and 3rd-order polynomials |

Answer» 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. |

A. | zero phase function |

B. | negative phase function |

C. | positive phase function |

D. | non-minimum phase function |

Answer» D. non-minimum phase function |

44. |
## Consider the function F (s)= 5/s(s2+3s+2), the initial value of f(t) is: |

A. | 5 |

B. | 5/2 |

C. | 5/3 |

D. | 0 |

Answer» 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: |

A. | limit the speed of the motor |

B. | limit the torque output of the motor |

C. | reduce the damping of the system |

D. | limit the acceleration of the motor |

Answer» 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: |

A. | minimum phase transfer function |

B. | non-minimum phase transfer function |

C. | minimum phase frequency response function |

D. | minimum gain transfer function |

Answer» A. minimum phase transfer function |

47. |
## State model representation is possible using _________ |

A. | physical variables |

B. | phase variables |

C. | canonical state variables |

D. | all of the above |

Answer» D. all of the above |

48. |
## Conventional control theory is applicable to ______ systems |

A. | siso |

B. | mimo |

C. | time varying |

D. | non-linear |

Answer» 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 |

A. | c(si-a)-1b+d |

B. | b(si-a)-1b+d |

C. | c(si-a)-1b+a |

D. | d(si-a)-1b+c |

Answer» A. c(si-a)-1b+d |

50. |
## The system which works on the initial condition without any input applied to it is called as : |

A. | homogeneous system |

B. | non homogeneous system |

C. | linear system |

D. | non linear system |

Answer» A. homogeneous system |

Done Studing? Take A Test.

Great job completing your study session! Now it's time to put your knowledge to the test. Challenge yourself, see how much you've learned, and identify areas for improvement. Don’t worry, this is all part of the journey to mastery. Ready for the next step? Take a quiz to solidify what you've just studied.