Explore topic-wise MCQs in Testing Subject.

This section includes 657 Mcqs, each offering curated multiple-choice questions to sharpen your Testing Subject knowledge and support exam preparation. Choose a topic below to get started.

1.

The constant M-circle represented by the equation x^2+2.25x+y^2=-1.25 has the value of M equal to:

A. 1
B. 2
C. 3
D. 4
Answer» D. 4
2.

A system has poles at 0.01 Hz, 1 Hz and 80Hz, zeroes at 5Hz, 100Hz and 200Hz. The approximate phase of the system response at 20 Hz is :

A. -90°
B. 0° c) 90°
C. d) -180°
Answer» B. 0° c) 90°
3.

In polar plots, what does each and every point represent w.r.t magnitude and angle?

A. scalar
B. vector
C. phasor
D. differentiator
Answer» D. differentiator
4.

If the system is represented by G(s) H(s) = k (s+7) / s (s +3) (s + 2), what would be its magnitude at ω = ∞?

A. 0
B. ∞ c) 7/10
C. d) 21
Answer» B. ∞ c) 7/10
5.

In polar plots, if a pole is added at the origin, what would be the value of the magnitude at Ω = 0?

A. zero
B. infinity
C. unity
D. unpredictable
Answer» C. unity
6.

Consider the system represented by the equation given below. What would be the total phase value at ω = 0?

A. -90°
B. -180°
C. -270°
D. -360°
Answer» D. -360°
7.

According to Nyquist stability criterion, where should be the position of all zeros of q(s) corresponding to s-plane?

A. on left half
B. at the center
C. on right half
D. random
Answer» B. at the center
8.

If a Nyquist plot of G (jω) H (jω) for a closed loop system passes through (-2, j0) point in GH plane, what would be the value of gain margin of the system in dB?

A. 0 db
B. 2.0201 db
C. 4 db
D. 6.0205 db
Answer» E.
9.

Which principle specifies the relationship between enclosure of poles & zeros by s- plane contour and the encirclement of origin by q(s) plane contour?

A. argument
B. agreement
C. assessment
D. assortment
Answer» B. agreement
10.

For Nyquist contour, the size of radius is

A. 25
B. 0
C. 1
D. ∞
Answer» E.
11.

For a stable closed loop system, the gain at phase crossover frequency should always be:

A. < 20 db
B. < 6 db
C. > 6 db
D. > 0 db
Answer» E.
12.

Nichol’s chart:

A. constant gain and constant phase shift loci of the closed-loop system.
B. plot of loop gain with the variation in frequency
C. circles of constant gain for the closed loop transfer function
D. circles of constant phase shift for the closed loop transfer function
Answer» C. circles of constant gain for the closed loop transfer function
13.

Constant N-loci:

A. constant gain and constant phase shift loci of the closed-loop system.
B. plot of loop gain with the variation in frequency
C. circles of constant gain for the closed loop transfer function
D. circles of constant phase shift for the closed loop transfer function
Answer» D. circles of constant phase shift for the closed loop transfer function
14.

Constant M- loci:

A. constant gain and constant phase shift loci of the closed-loop system.
B. plot of loop gain with the variation in frequency
C. circles of constant gain for the closed loop transfer function
D. circles of constant phase shift for the closed loop transfer function
Answer» E.
15.

Which one of the following methods can determine the closed loop system resonance frequency operation?

A. root locus method
B. nyquist method
C. bode plot
D. m and n circle
Answer» E.
16.

Scientist Nyquist have contribution in:

A. asymptotic plots
B. polar plots
C. root locus technique
D. constant m and n circle
Answer» C. root locus technique
17.

Scientist Evans have contribution in :

A. asymptotic plots
B. polar plots
C. root locus technique
D. constant m and n circle
Answer» D. constant m and n circle
18.

Scientist Bode have contribution in :

A. asymptotic plots
B. polar plots
C. root locus technique
D. constant m and n circle
Answer» B. polar plots
19.

If the gain of the open loop system is doubled, the gain of the system is :

A. not affected
B. doubled
C. halved
D. one fourth of the original value
Answer» B. doubled
20.

Negative exponential term in the equation of the transfer function causes the transportation lag.

A. true
B. false
Answer» B. false
21.

Rate compensation :

A. increases bandwidth
B. attenuation
C. increases damping factor
D. second order
Answer» D. second order
22.

Lag-lead compensation is a:

A. increases bandwidth
B. attenuation
C. increases damping factor
D. second order
Answer» E.
23.

Lead compensation leads to:

A. increases bandwidth
B. attenuation
C. increases damping factor
D. second order
Answer» B. attenuation
24.

Derivative error compensation:

A. improvement in transient response
B. reduction in steady state error
C. reduction is settling time
D. increase in damping constant
Answer» E.
25.

Derivative output compensation:

A. improvement in transient response
B. reduction in steady state error
C. reduction is settling time
D. increase in damping constant
Answer» D. increase in damping constant
26.

Addition of zero at origin:

A. improvement in transient response
B. reduction in steady state error
C. reduction is settling time
D. increase in damping constant
Answer» B. reduction in steady state error
27.

Lag compensation leads to:

A. increases bandwidth
B. attenuation
C. increases damping factor
D. second order
Answer» C. increases damping factor
28.

Systems of type higher than 2 are not employed in practice.

A. true
B. false
Answer» B. false
29.

A particular control system yielded a steady state error of 0.20 for unit step input. A unit integrator is cascaded to this system and unit ramp input is applied to this modified system. What is the value of steady- state error for this modified system?

A. 0.10
B. 0.15
C. 0.20
D. 0.25
Answer» E.
30.

A ramp input applied to a unity feedback system results in 5% steady state error. The type number and zero frequency gain of the system are respectively

A. 1 and 20
B. 0 and 20
C. 0 and 1/20
D. 1 and 1/20
Answer» B. 0 and 20
31.

Consider the unity feedback system with open loop transfer function the minimum value of the steady state error to a ramp input r(t) = 6tu(t) is OLTF = K/s(s+1)(s+2)

A. 1
B. 2
C. 3
D. 4
Answer» C. 3
32.

The system in originally critically damped if the gain is doubled the system will be :

A. remains same
B. overdamped
C. under damped
D. undamped
Answer» D. undamped
33.

The steady state error for a unity feedback system for the input r(t) = Rt^2/2 to the system G(s) = K(s+2)/s(s3+7s2+12s) is

A. 0
B. 6r/k
C. ∞
D. 3r/k
Answer» C. ∞
34.

For non-unity feedback system, the error is calculated with respect to the reference signal.

A. true
B. false
Answer» C.
35.

On which of the following factors does the sensitivity of a closed loop system to gain changes and load disturbances depend?

A. frequency
B. loop gain
C. forward gain
D. all of the mentioned
Answer» E.
36.

A control system with excessive noise, is likely to suffer from

A. saturation in amplifying stages
B. loss of gain
C. vibrations
D. oscillations
Answer» B. loss of gain
37.

The output of a feedback control system must be a function of

A. reference and output
B. reference and input
C. input and feedback signal
D. output and feedback signal
Answer» E.
38.

Regenerative feedback implies feedback with

A. oscillations
B. step input
C. negative sign
D. positive sign
Answer» E.
39.

The relationship between an input and output variable of a signal flow graph is given by the net gain between the input and output node is known as the overall

A. overall gain of the system
B. stability
C. bandwidth
D. speed
Answer» B. stability
40.

Loop which do not possess any common node are said to be                        loops.

A. forward gain
B. touching loops
C. non touching loops
D. feedback gain
Answer» D. feedback gain
41.

A signal flow graph is the graphical representation of the relationships between the variables of set linear algebraic equations.

A. true
B. false
Answer» B. false
42.

Which of the following is not the feature of modern control system?

A. quick response
B. accuracy
C. correct power level
D. no oscillation
Answer» E.
43.

Primary purpose of using Feedback is :

A. to reduce the sensitivity of the system to parameter variations.
B. to increase the bandwidth of the system
C. to reduce the noise and distortion of the system
D. to increase stability of the system
Answer» B. to increase the bandwidth of the system
44.

The output of the feedback control system must be a function of:

A. reference input
B. reference output
C. output and feedback signal
D. input and feedback signal
Answer» E.
45.

Determine the sensitivity of the overall transfer function for the system shown in the figure below, at w=1 rad/sec with respect to the feedback path transfer function.

A. 1.11
B. -1.11
C. 2.22
D. -2.22
Answer» C. 2.22
46.

For the gain feedback system, does not affect the system output if KG is :

A. small
B. negative
C. one
D. very large
Answer» E.
47.

Open loop system is                        stable than closed loop system

A. more
B. less
C. inclined
D. exponential
Answer» B. less
48.

Insertion of negative feedback in control system affects:

A. the transient response to vanish uniformly
B. the transient response to decay very fast
C. no change in transient response
D. the transient response decays at slow rate
Answer» C. no change in transient response
49.

As compared to the closed loop system, an open loop system is

A. more stable but less accurate
B. less stable as well as less accurate
C. more stable as well as more accurate
D. less stable but more accurate
Answer» B. less stable as well as less accurate
50.

Which of the following will not decrease as a result of introduction of negative feedback?

A. instability
B. bandwidth
C. overall gain
D. distortion
Answer» C. overall gain