MCQOPTIONS
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MCQOPTIONS
This section includes 646 Mcqs, each offering curated multiple-choice questions to sharpen your ENGINEERING SERVICES EXAMINATION (ESE) knowledge and support exam preparation. Choose a topic below to get started.
| 151. |
The entries in the first column of Routh array of a fourth order are 5, 2, - 0.1, 2, 1. The number of poles in the right half plane are |
| A. | 1 |
| B. | 2 |
| C. | 3 |
| D. | 4 |
| Answer» C. 3 | |
| 152. |
Assertion (A): Integral control action is sometimes called reset control.Reason (R): Reset rate is expressed as number of repeats per unit time. |
| A. | Both A and R are correct and R is correct explanation of A |
| B. | Both A and R are correct but R is not correct explanation of A |
| C. | A is correct but R is wrong |
| D. | R is correct but A is wrong |
| Answer» C. A is correct but R is wrong | |
| 153. |
In force voltage analogy the quantity analogous to spring constant K is |
| A. | R |
| B. | C |
| C. | L |
| D. | 1/C |
| Answer» E. | |
| 154. |
Assertion (A): An on off controller gives rise to oscillation of the output between two limits.Reason (R): Location of a pair of poles on jω axis gives rise to self sustained oscillations in the output. |
| A. | Both A and R are correct and R is correct explanation of A |
| B. | Both A and R are correct but R is not correct explanation of A |
| C. | A is correct but R is wrong |
| D. | R is correct but A is wrong |
| Answer» C. A is correct but R is wrong | |
| 155. |
The effect of negative feedback on distortion and bandwidth because |
| A. | both are decreased |
| B. | both are increased |
| C. | distortion is reduced and bandwidth is increased |
| D. | distortion is increased and bandwidth is decreased |
| Answer» D. distortion is increased and bandwidth is decreased | |
| 156. |
Stepper motors find applications in |
| A. | X-Y plotters |
| B. | numerically controlled machining equipment |
| C. | printers |
| D. | all of the above |
| Answer» E. | |
| 157. |
A network has G(s) as under, Then |
| A. | it is lead network |
| B. | it is lag network |
| C. | it is lead network if T1 > T2 and lag network T1 < T2 |
| D. | it is lead network if T1 < T2 and lag network T1 > T2 |
| Answer» D. it is lead network if T1 < T2 and lag network T1 > T2 | |
| 158. |
Assertion (A): Derivative control action cannot be used alone.Reason (R): Derivative control action is effective only during transient periods. |
| A. | Both A and R are correct and R is correct explanation of A |
| B. | Both A and R are correct but R is not correct explanation of A |
| C. | A is correct but R is wrong |
| D. | R is correct but A is wrong |
| Answer» B. Both A and R are correct but R is not correct explanation of A | |
| 159. |
The current rating of dc tachogenerator is usually |
| A. | small |
| B. | high |
| C. | medium |
| D. | either (b) or (c) |
| Answer» B. high | |
| 160. |
Consider the following systems. (where C(s) is the output and R(s) is the input of these systems) |
| A. | System I has larger bandwidth and faster speed of response than System II |
| B. | System II has larger bandwidth and faster speed of response than System I |
| C. | System I has larger bandwidth but System II has faster speed of response |
| D. | System II has larger bandwidth but System I has faster speed of response |
| Answer» B. System II has larger bandwidth and faster speed of response than System I | |
| 161. |
In a second order system, peak overshoot is independent of |
| A. | damping factor |
| B. | natural frequency |
| C. | both damping factor and natural frequency |
| D. | neither damping factor nor natural frequency |
| Answer» C. both damping factor and natural frequency | |
| 162. |
The pole zero plot in the given figure is for |
| A. | non-minimum phase function |
| B. | minimum phase function |
| C. | all pass function |
| D. | either (a) or (b) |
| Answer» D. either (a) or (b) | |
| 163. |
Assertion (A): Temperature control of the passenger compartment of car uses both feed forward and feedback controls.Reason (R): Feed forward control gives corrective action before the disturbance affects the output and feedback control applies corrective action after output changes. |
| A. | Both A and R are correct and R is correct explanation of A |
| B. | Both A and R are correct but R is not correct explanation of A |
| C. | A is correct but R is wrong |
| D. | R is correct but A is wrong |
| Answer» B. Both A and R are correct but R is not correct explanation of A | |
| 164. |
Assertion (A): The transient performance of a control system is generally analysed by using unit step function as reference input.Reason (R): Impulse is the most common input found in practice. |
| A. | Both A and R are correct and R is correct explanation of A |
| B. | Both A and R are correct but R is not correct explanation of A |
| C. | A is correct but R is wrong |
| D. | R is correct but A is wrong |
| Answer» B. Both A and R are correct but R is not correct explanation of A | |
| 165. |
Assertion (A): Nyquist stability criterion uses the number of encirclements around (-1 + j0) point in GH plane to determine stabilityReason (R): The (-1 + j0) point in the s plane lies in the Nyquist path. |
| A. | Both A and R are correct and R is correct explanation of A |
| B. | Both A and R are correct but R is not correct explanation of A |
| C. | A is correct but R is wrong |
| D. | R is correct but A is wrong |
| Answer» D. R is correct but A is wrong | |
| 166. |
For a second order system, the position of poles is shown in the given figure. This system is |
| A. | undamped |
| B. | overdamped |
| C. | underdamped |
| D. | critically damped |
| Answer» D. critically damped | |
| 167. |
Generally a servomotor operates at |
| A. | high torque and high speed |
| B. | low torque and low speed |
| C. | low torque and high speed |
| D. | high torque and low speed |
| Answer» D. high torque and low speed | |
| 168. |
For a factor 1/(jω)² in the transfer function, the log magnitude plot |
| A. | is a straight line with slope 0 dB/decade |
| B. | is a straight line with slope 20 dB/decade |
| C. | is a straight line with slope - 20 dB/decade |
| D. | is a straight line with slope - 40 dB/decade |
| Answer» E. | |
| 169. |
Consider the following expressions which indicate the step or impulse response of an initially relaxed system. Those which correspond to the step and impulse response of the same system include |
| A. | 1 and 3 |
| B. | 1 and 4 |
| C. | 2 and 4 |
| D. | 2 and 3 |
| Answer» B. 1 and 4 | |
| 170. |
For very low frequencies, log magnitude for the given figure is |
| A. | 0 dB |
| B. | -3 dB |
| C. | 3 dB |
| D. | 10 dB |
| Answer» D. 10 dB | |
| 171. |
The number of stator field windings in an ac tachometer are |
| A. | 1 |
| B. | 2 |
| C. | 3 |
| D. | 4 |
| Answer» C. 3 | |
| 172. |
For the system in the given figure R(s) = 1/s . Then steady state error is |
| A. | 1/(1+K) |
| B. | K |
| C. | Zero |
| D. | 1 |
| Answer» D. 1 | |
| 173. |
The primary function of lag compensator is to provide sufficient |
| A. | gain margin |
| B. | phase margin |
| C. | both gain margin and phase margin |
| D. | either (a) or (b) |
| Answer» C. both gain margin and phase margin | |
| 174. |
The resolution of a wire wound potentiometer is about |
| A. | 0.001% |
| B. | 0.1% |
| C. | 1% |
| D. | 5% |
| Answer» C. 1% | |
| 175. |
For the factor (1 + 0.5 jω) the corner frequency is |
| A. | 1 rad/sec |
| B. | 0.5 rad/sec |
| C. | 2 rad/sec |
| D. | 0.25 rad/sec |
| Answer» D. 0.25 rad/sec | |
| 176. |
Assertion (A): In simplifying block diagram the product of transfer functions in feed forward direction must remain the same.Reason (R): In simplifying block diagram the product of transfer functions around a closed loop must remain the same. |
| A. | Both A and R are correct and R is correct explanation of A |
| B. | Both A and R are correct but R is not correct explanation of A |
| C. | A is correct but R is wrong |
| D. | R is correct but A is wrong |
| Answer» C. A is correct but R is wrong | |
| 177. |
For an RLC series circuit Z(s) is of the form |
| A. | A |
| B. | B |
| C. | C |
| D. | D |
| Answer» E. | |
| 178. |
For the function G(s) H(s) = 1/s(s+1)(s+0.5) the phase cross-over frequency is |
| A. | 0.5 rad/sec |
| B. | 0.707 rad/sec |
| C. | 1.732 rad/sec |
| D. | 2 rad/sec |
| Answer» C. 1.732 rad/sec | |
| 179. |
In terms of ξ and ωn the settling time of a second order systems for 2% criterion and step input is equal to |
| A. | 1/ξωn |
| B. | 2/ξωn |
| C. | 3/ξωn |
| D. | 4/ξωn |
| Answer» E. | |
| 180. |
In the given figure, the number of individual loops is |
| A. | 2 |
| B. | 4 |
| C. | 5 |
| D. | 6 |
| Answer» D. 6 | |
| 181. |
The static equation of a system is given below. The poles of this system are located at |
| A. | -1, -9 |
| B. | -1, -20 |
| C. | -4, -5 |
| D. | -9, -20 |
| Answer» D. -9, -20 | |
| 182. |
In Bode analysis the correction at corner frequency is 3 dB. |
| A. | True |
| B. | False |
| C. | May be True or False |
| D. | can't say |
| Answer» B. False | |
| 183. |
The log magnitude for the system in the given figure is (where T = RC) |
| A. | 20 log (1 + ωT) |
| B. | -20 log (1 + ωT) |
| C. | -10 log (1 + ω²T²) |
| D. | -20 log (1 + ω²T²) |
| Answer» D. -20 log (1 + ω²T²) | |
| 184. |
Assertion (A): A large negative feedback is deliberately introduced in an amplifier to make its gain independent of variation in parameters of active device.Reason (R): A large negative value of feedback results in a high value of return difference compared to unity which makes the feedback gain inversely proportional to the feedback factor. |
| A. | Both A and R are correct and R is correct explanation of A |
| B. | Both A and R are correct but R is not correct explanation of A |
| C. | A is correct but R is wrong |
| D. | R is correct but A is wrong |
| Answer» B. Both A and R are correct but R is not correct explanation of A | |
| 185. |
Integral error compensation changes a second order system to |
| A. | first order system |
| B. | third order system |
| C. | fourth order system |
| D. | either (a) or (b) depending on the system |
| Answer» C. fourth order system | |
| 186. |
The transfer function G(s) of a PID controller is |
| A. | A |
| B. | B |
| C. | C |
| D. | D |
| Answer» B. B | |
| 187. |
Optical encoders most commonly used in control systems are |
| A. | absolute encoders |
| B. | secondary encoders |
| C. | incremental encoders |
| D. | none of the above |
| Answer» D. none of the above | |
| 188. |
For the following function, the poles are at |
| A. | s = 0 and s = ∞ |
| B. | s = j2nπ where n = 0, 1, 2 |
| C. | s = ± j2nπ where n = 0, 1, 2.. |
| D. | none of the above |
| Answer» D. none of the above | |
| 189. |
In the given figure the input frequency f = 10(1/2 π RC) |
| A. | 0 dB |
| B. | 3 dB |
| C. | -3 dB |
| D. | -20 dB |
| Answer» E. | |
| 190. |
From the noise point of view, bandwidth should |
| A. | be large |
| B. | not be too large |
| C. | should be as large as possible |
| D. | should be infinite |
| Answer» C. should be as large as possible | |
| 191. |
Assertion (A): If integral control action is included in the controller the offset can be eliminated.Reason (R): Integral control action may lead to oscillatory response. |
| A. | Both A and R are correct and R is correct explanation of A |
| B. | Both A and R are correct but R is not correct explanation of A |
| C. | A is correct but R is wrong |
| D. | R is correct but A is wrong |
| Answer» C. A is correct but R is wrong | |
| 192. |
Assertion (A): F(s) is valid throughout s plane except at poles of F(s).Reason (R): £[f1(t) + f2(t)] = £[f1(t)] + £[f2(t)] |
| A. | Both A and R are correct and R is correct explanation of A |
| B. | Both A and R are correct but R is not correct explanation of A |
| C. | A is correct but R is wrong |
| D. | R is correct but A is wrong |
| Answer» C. A is correct but R is wrong | |
| 193. |
The most commonly used devices for differencing and amplification, in control systems, are |
| A. | BJT amplifiers |
| B. | FET amplifiers |
| C. | operational amplifiers |
| D. | either (a) or (b) |
| Answer» D. either (a) or (b) | |
| 194. |
If G(s)H(s) = K (T₁s + 1)/[s² (T₂s + 1)] the system stability depended an relative magnitudes of T₁ and T₂. |
| A. | True |
| B. | False |
| C. | May be True or False |
| D. | can't say |
| Answer» B. False | |
| 195. |
Polar plot of a lag-lead compensator is a circle. |
| A. | True |
| B. | False |
| C. | May be True or False |
| D. | can't say |
| Answer» B. False | |
| 196. |
The open loop frequency response of a unity feed back system is as given below. The gain margin and phase margin respectively are |
| A. | 20 dB and 15° |
| B. | 20 dB and 25° |
| C. | 6 dB and 15° |
| D. | 6 dB and 25° |
| Answer» D. 6 dB and 25° | |
| 197. |
Which of the following can act as error detecting devices 1. a pair of potentiometers2. a pair of synchros3. a differential transformer4. a metadyne5. a control transformer Select the answer using the following codes: |
| A. | 1, 2, 5 |
| B. | 2, 3, 4, 5 |
| C. | 1, 3, 4, 5 |
| D. | 1, 2, 3, 4 |
| Answer» B. 2, 3, 4, 5 | |
| 198. |
Consider the following statements: 1. The positiveness of coefficients of characteristic equation is necessary as well as sufficient condition for stability of first and second order systems.2. The positiveness of coefficients of characteristic equation ensures negativeness of real roots but is not sufficient condition for stability of third and higher order systems. Out of above statements: |
| A. | only 1 is correct |
| B. | both 1 and 2 are correct |
| C. | only 2 is correct |
| D. | both are wrong |
| Answer» C. only 2 is correct | |
| 199. |
The correct sequence of events to improve system stability is |
| A. | insert derivative action, use negative feedback, reduce gain |
| B. | reduce gain, use negative feedback, insert derivative action |
| C. | reduce gain, insert derivative feedback, use negative feed back |
| D. | use negative feedback, reduce gain, insert derivative action |
| Answer» E. | |
| 200. |
Transfer functions of even complicated components can be found by frequency response tests. |
| A. | True |
| B. | False |
| C. | May be True or False |
| D. | can't say |
| Answer» B. False | |