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.
| 351. |
Whether a linear system is stable or unstable that it |
| A. | is a property of the system only |
| B. | depends on the input function only |
| C. | both (a) and (b) |
| D. | either (a) or (b) |
| Answer» B. depends on the input function only | |
| 352. |
The polar plot of the given figure is for the term |
| A. | A |
| B. | B |
| C. | C |
| D. | D |
| Answer» D. D | |
| 353. |
Which of the following is not correct for two phase servomotor? |
| A. | Rotor diameter is small |
| B. | Applied voltages are seldom balanced |
| C. | Rotor resistance is low |
| D. | Torque speed curve is linear |
| Answer» D. Torque speed curve is linear | |
| 354. |
In a second order system ωn = 10 rad/sec and ζ = 0.1, then ωd = |
| A. | 9.1 rad/sec |
| B. | 9.95 rad/sec |
| C. | 9 rad/sec |
| D. | 1 rad/sec |
| Answer» C. 9 rad/sec | |
| 355. |
In a second order system, the time constant t of exponential envelopes depends |
| A. | only on damping factor |
| B. | only on natural frequency |
| C. | both on damping factor and natural frequency |
| D. | neither on damping factor nor on natural frequency |
| Answer» D. neither on damping factor nor on natural frequency | |
| 356. |
Which dc servomotor has minimum inertia? |
| A. | Slotted armature construction |
| B. | Surface wound armature |
| C. | Surface wound with stationary rotor |
| D. | Either (a) or (b) |
| Answer» D. Either (a) or (b) | |
| 357. |
A lead compensator is basically a |
| A. | high pass filter |
| B. | low pass filter |
| C. | band stop filter |
| D. | none of the above |
| Answer» B. low pass filter | |
| 358. |
The polar plot in the given figure is for G(jω) = |
| A. | A |
| B. | B |
| C. | C |
| D. | D |
| Answer» D. D | |
| 359. |
The magnitude of transport lag factor is always zero. |
| A. | True |
| B. | False |
| C. | May be True or False |
| D. | can't say |
| Answer» C. May be True or False | |
| 360. |
A unity feedback system has G(s) = 10/s(s+1)(s+2). If input r(t) = 1 + 2t + 3/2t³, the steady error is |
| A. | zero |
| B. | 0.4 |
| C. | 4 |
| D. | infinity |
| Answer» E. | |
| 361. |
M circles are symmetrical with respect to real axis. |
| A. | True |
| B. | False |
| C. | May be True or False |
| D. | can't say |
| Answer» B. False | |
| 362. |
If damping ratio is 0.5, the lines joining complex poles with origin are inclined to negative real axis at |
| A. | ± 90° |
| B. | ± 60° |
| C. | ± 45° |
| D. | ± 30° |
| Answer» C. ± 45° | |
| 363. |
The capacitance of a gas pressure vessel is defined as |
| A. | (change in gas stored) / (change in gas pressure) |
| B. | (change in gas pressure) / (change in gas stored) |
| C. | (change in gas stored) x (change in gas pressure) |
| D. | none of the above |
| Answer» B. (change in gas pressure) / (change in gas stored) | |
| 364. |
The gain margin for a stable system |
| A. | has a positive decibel value |
| B. | has a negative decibel value |
| C. | has a large negative decibel value |
| D. | none of the above |
| Answer» B. has a negative decibel value | |
| 365. |
Assertion (A): Feedback control systems offer more accurate control than open loop systems.Reason (R): The feedback path establishes a link for comparison of input and output and subsequent error correction. |
| 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 | |
| 366. |
Nyquist stability criterion is based on a theorem from the theory of complex variables. |
| A. | True |
| B. | False |
| C. | May be True or False |
| D. | can't say |
| Answer» B. False | |
| 367. |
A second order system exhibits 100% overshoot. The damping ratio is |
| A. | 0 |
| B. | 1 |
| C. | < 1 |
| D. | > 1 |
| Answer» B. 1 | |
| 368. |
The number of branches of root locus plot is equal to |
| A. | the number of roots of characteristic equation |
| B. | double the number of roots of characteristic equation |
| C. | the number of roots of characteristic equation minus one |
| D. | the number of roots of characteristic equation plus one |
| Answer» B. double the number of roots of characteristic equation | |
| 369. |
The addition of a zero to the open loop transfer function |
| A. | pulls the root locus to the left and makes the system more stable |
| B. | pulls the root locus to the right and makes the system less stable |
| C. | either (a) or (b) |
| D. | neither (a) nor (b) |
| Answer» B. pulls the root locus to the right and makes the system less stable | |
| 370. |
A second order system has damping ratio x and natural frequency ωn. The unit step response is |
| A. | A |
| B. | B |
| C. | C |
| D. | D |
| Answer» D. D | |
| 371. |
The units of thermal capacitance are |
| A. | k cal/°C |
| B. | °C/k cal |
| C. | °C sec/k cal |
| D. | none of the above |
| Answer» B. °C/k cal | |
| 372. |
For a stable system having two or more gain crossover frequencies the phase margin is measured |
| A. | at lowest gain crossover frequency |
| B. | at highest gain crossover frequency |
| C. | at the gain crossover frequencies |
| D. | none of the above |
| Answer» C. at the gain crossover frequencies | |
| 373. |
The given figure shows a constant current source driving a parallel RC circuit. It is equivalent to |
| A. | a lag network |
| B. | a lead network |
| C. | a lag-lead network |
| D. | either (a) or (b) |
| Answer» B. a lead network | |
| 374. |
The transfer function 1/(1+jωT) has the characteristics of high pass filter. |
| A. | True |
| B. | False |
| C. | May be True or False |
| D. | can't say |
| Answer» C. May be True or False | |
| 375. |
I-PD controlled system has |
| A. | I, P and D actions in forward path |
| B. | I, P and D actions in feedback path |
| C. | I action in forward path but P and D action in feedback path |
| D. | I action in feedback path but P and D actioins in forward path |
| Answer» D. I action in feedback path but P and D actioins in forward path | |
| 376. |
A stepper motor is |
| A. | a two phase induction motor |
| B. | is a kind of rotating amplifier |
| C. | is an electromagnetic transducer used to convert an angular position of shaft into electrical signal |
| D. | is an electromechanical device which actuates a train of step angular movements in response to a train of input pulses on one to one basis |
| Answer» E. | |
| 377. |
The slope of log-magnitude asymptote changes by - 40 dB/ decade at a frequency ω₁. This means that |
| A. | a double pole is present |
| B. | a pair of complex conjugate poles is present |
| C. | either a double pole or a pair of complex conjugate poles is present |
| D. | a pole or zero at origin is present |
| Answer» D. a pole or zero at origin is present | |
| 378. |
An electromechanical device which actuates a train of step angular movements in response to a train of input pulses on one to one basis is |
| A. | synchro control transformer |
| B. | LVDT |
| C. | stepper motor |
| D. | tacho generator |
| Answer» D. tacho generator | |
| 379. |
The log magnitude curve for a constant gain K is a horizontal straight line at a magnitude 20 log K dB. |
| A. | True |
| B. | False |
| C. | May be True or False |
| D. | can't say |
| Answer» B. False | |
| 380. |
A unity feedback system has open loop transfer function 1/(s+5)s . The closed loop transfer function is |
| A. | A |
| B. | B |
| C. | C |
| D. | D |
| Answer» D. D | |
| 381. |
For the transport lag G(jω) = e^(-jωT), the polar plot is |
| A. | a semi circle |
| B. | a circle |
| C. | a unit circle |
| D. | none of the above |
| Answer» D. none of the above | |
| 382. |
If G(s)H(S) = K(s+6)/(s+3)(s+5) the breakaway and break in points in the root locus are located at |
| A. | -2 and -1 |
| B. | -2.47 and -3.77 |
| C. | -4.27 and -7.73 |
| D. | none of the above |
| Answer» D. none of the above | |
| 383. |
For the system shown in the given figure the time response to unit step input is |
| A. | A |
| B. | B |
| C. | C |
| D. | D |
| Answer» D. D | |
| 384. |
Assertion (A): In liquid system the ratio of change in liquid level to change in flow rate is called resistance of liquid flow.Reason (R): In liquid level systems the ratio of change in liquid stored in a tank to the change in head is called capacitance of tank. |
| 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 | |
| 385. |
For the characteristic equation s⁵ + s⁴ + 2s³ + 2s² + 3s + 15 = 0, the number of roots in left half s plane are |
| A. | 1 |
| B. | 2 |
| C. | 3 |
| D. | 5 |
| Answer» D. 5 | |
| 386. |
The polar plot of transport lag is a unit circle. |
| A. | True |
| B. | False |
| C. | May be True or False |
| D. | can't say |
| Answer» B. False | |
| 387. |
If Z is the number of zeros of 1 + G(s) H(s) in the right half s plane. N is the number of clockwise encircle elements of (-1 + jo) point. P is the number of poles of G(s) H(s) in right half s plane. The Nyquist stability criterion can be expressed as |
| A. | Z = N + P |
| B. | Z = P/N |
| C. | Z = N - P |
| D. | Z = PN |
| Answer» B. Z = P/N | |
| 388. |
For stable network the real parts of poles and zeros of driving point functions must be |
| A. | negative |
| B. | negative or zero |
| C. | zero |
| D. | positive |
| Answer» C. zero | |
| 389. |
Consider the following statements about transport-lag 1. It is of non-minimum phase behaviour2. It normally exists in thermal, hydraulic and pneumatic systems3. It has an excessive phase lag with no attenuation at high frequency Which of the above statements are correct? |
| A. | 1 only |
| B. | 1 and 2 |
| C. | All |
| D. | 2 and 3 |
| Answer» D. 2 and 3 | |
| 390. |
Consider the following statements about polar plots 1. Addition of a non-zero pole to a transfer function results in further rotation of polar plot through an angle of - 90° as ω → ∞2. Addition of a pole at the origin to a transfer function rotates the polar plot at zero and infinite frequencies by a further angle of - 90° Of the above statements: |
| A. | Both are correct |
| B. | Both are wrong |
| C. | 1 is correct and 2 is wrong |
| D. | 2 is correct and 1 is wrong |
| Answer» B. Both are wrong | |
| 391. |
Which of the following can be used as a rotating amplifier in a control system? 1. Amplidyne2. Separately excited dc generator3. Synchro4. Self excited dc generator Select the answer from the following codes: |
| A. | 3 and 4 |
| B. | 1 and 2 |
| C. | 1, 2 and 3 |
| D. | all |
| Answer» C. 1, 2 and 3 | |
| 392. |
Which control action is also called rate control? |
| A. | Proportional |
| B. | Derivative |
| C. | Integral |
| D. | Proportional plus integral |
| Answer» C. Integral | |
| 393. |
In a lag network the input frequency is 100 fc where fc is critical frequency. The voltage gain is |
| A. | 0 dB |
| B. | -20 dB |
| C. | -40 dB |
| D. | -60 dB |
| Answer» D. -60 dB | |
| 394. |
Assertion (A): The part of root locus on the real axis is not dependent on the poles and zeros which are not on the real axis.Reason (R): Poles and zeros which are not on the real axis occur in conjugate pairs |
| 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 | |
| 395. |
Accurate amplitude measurements can be made more easily than accurate phase shift measurements. |
| A. | True |
| B. | False |
| C. | May be True or False |
| D. | can't say |
| Answer» B. False | |
| 396. |
For the feedback system with closed loop transfer function given below, the settling time for 2% tolerance |
| A. | A |
| B. | B |
| C. | C |
| D. | D |
| Answer» D. D | |
| 397. |
For the transport lag G(jω) = e^(-jωT), the phase angle |
| A. | is constant |
| B. | varies linearly with frequency |
| C. | varies linearly with low frequencies only |
| D. | values as per square law |
| Answer» C. varies linearly with low frequencies only | |
| 398. |
For the system of the given figure |G(jω)| = 0 dB at ω = |
| A. | 0 |
| B. | 1 rad/sec |
| C. | ∞ |
| D. | 2.38 rad/sec |
| Answer» E. | |
| 399. |
In op-amp circuit of the given figure, Eo(s)/Ei(s) = |
| A. | A |
| B. | B |
| C. | C |
| D. | D |
| Answer» B. B | |
| 400. |
For a type 0 system and unit ramp input, the steady state error is |
| A. | 0 |
| B. | ∞ |
| C. | 1 |
| D. | 1/KV |
| Answer» C. 1 | |