Circles of constant gain for the closed loop transfer function

Constant gain and constant phase shift loci of the closed-loop system.

Plot of loop gain with the variation in frequency

Circles of constant gain for the closed loop transfer function

Circles of constant phase shift for the closed loop transfer function

Which one of the following statements is correct?Nichol’s chart is useful for the detailed study of:

Close loop and open loop frequency responses

Loop transfer function of a feedback system is \(G\left( s \right)H\left( s \right) = \frac{{s + 3}}{{{s^2}\left( {s - 3} \right)}}\;.\) Take the Nyquist contour in the clockwise direction. Then, the Nyquist plot of G(s) H(s) encircles \(- 1 + j0\)

once in anticlockwise direction

twice in anticlockwise direction

Consider two control systems with the following transfer functionsSystem 1: \(G\left( s \right) = \frac{1}{{3s + 1}}\) System 2: \(G\left( s \right) = \frac{1}{{s + 1}}\) Which of the following is true?

Bandwidth of both the systems are same

Bandwidth of System 1 is greater than bandwidth of System 2

Bandwidth of System 2 is greater than bandwidth of System 1

Bandwidth of both the systems are same

Both the systems have infinite bandwidth

If the gain margin of a system in decibels is negative, the system is:

Could be stable or unstable or marginally stable

Assertion (A): The stability analysis of systems with dead time can be conducted easily using the Bode plots.Reason (R): The magnitude plot of a system is unaffected by the presence of dead time.

Both (A) and (R) are true, but (R) is not the correct explanation of (A).

Both (A) and (R) are true and (R) is the correct explanation of (A).

Both (A) and (R) are true, but (R) is not the correct explanation of (A).

An all pass network imparts only

+/–90 degree phase shift to the input

+/–180 degree phase shift to the input

A family of constant N circles has the centre as

\(X=-\dfrac{1}{4} \ \text{and} \ Y = 4 \ N\)

\(X=-\dfrac{1}{2} \ \text{and} \ Y=\dfrac{1}{4N}\)

\(X=-\dfrac{1}{2} \ \text{and} \ Y=\dfrac{1}{2N}\)

A single-input single-output feedback system has forward transfer function G(s) and feedback transfer function H(s). It is given that |G(s)H(s)| < 1. Which of the following is true about the stability of the system?

It is not possible to say whether or not the system is stable from the information given

The system is stable if all zeros of G(s)H(s) are in left half of the s-plane

The system is stable if all poles of G(s)H(s) are in left half of the s-plane

It is not possible to say whether or not the system is stable from the information given

Consider the following asymptotic Bode magnitude plot ( \(\omega\) is in rad/s).Which one of the following transfer functions is best represented by the above Bode magnitude plot?

\(\frac{{4\left( {1 + 0.5s} \right)}}{{s\left( {1 + 0.25s} \right)}}\)

\(\frac{{2s}}{{\left( {1 + 0.5s} \right){{\left( {1 + 0.25s} \right)}^2}}}\)

\(\frac{{4\left( {1 + 0.5s} \right)}}{{s\left( {1 + 0.25s} \right)}}\)

\(\frac{{2s}}{{\left( {1 + 2s} \right)\left( {1 + 4s} \right)}}\)

\(\frac{{4s}}{{\left( {1 + 2s} \right){{\left( {1 + 4s} \right)}^2}}}\)

In bode plot, systems with dead time

Introduces phase angle of \(\frac{{\omega {\tau _d} \times 180^\circ }}{\pi }\) in phase plot

Introduces phase angle of \(\frac{{ - \omega {\tau _d} \times 180^\circ }}{\pi }\) in phase plot

Introduces phase angle of \(\frac{{\omega {\tau _d} \times 180^\circ }}{\pi }\) in phase plot

Introduces phase angle of \(\frac{{\omega {\tau _d}}}{\pi }\) in phase plot

A transfer function having all its poles and zeroes only in the left half of the s-plane is called

a minimum-phase transfer function

a maximum-phase transfer function

In control systems, excessive bandwidth is NOT employed because:

it leads to low relative stability

noise is proportional to bandwidth

it leads to low relative stability

noise is proportional to the square of the bandwidth

By adding a pole at the origin of s-plane, the Nyquist plot of a system will rotate by

180° in anti-clockwise direction

90° in anti-clockwise direction

180° in anti-clockwise direction

Directions: It consists of two statements, one labelled as the ‘Statement (I)’ and the other as ‘Statement (II)’. Examine these two statements carefully and select the answers to these items using the codes given below:Statement (I):The polar plot has limitation for portraying the frequency response of a system.Statement (II):The calculation of frequency response is tedious and does not indicate the effect of the individual poles and zeros.

Both Statement (I) and Statement (II) are individually true and Statement (II) is the correct explanation of Statement (I)

Both Statement (I) and Statement (II) are individually true but Statement (II) is not the correct explanation of Statement (I)

Statement (I) is true but Statement (II) is false

Statement (I) is false but Statement (II) is true

A transfer function has its zeros in the right half of the s plane. The function

will give stable impulse response

93 + Mcqs in Frequency Response in Electronic Devices Circuits Page 1 McqOptions

1.	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

Discussion

2.	Which one of the following statements is correct?Nichol’s chart is useful for the detailed study of:
A.	Closed loop frequency response
B.	Open loop frequency response
C.	Close loop and open loop frequency responses
D.	None of the mentioned
Answer» B. Open loop frequency response

Discussion

3.	A system has fourteen poles and two zeros. Its high frequency asymptote in its magnitude plot having a slope of
A.	-40 dB/ decade
B.	-240 dB/ decade
C.	–280 dB/decade
D.	–320 dB/ decade
Answer» C. –280 dB/decade

Discussion

4.	Loop transfer function of a feedback system is \(G\left( s \right)H\left( s \right) = \frac{{s + 3}}{{{s^2}\left( {s - 3} \right)}}\;.\) Take the Nyquist contour in the clockwise direction. Then, the Nyquist plot of G(s) H(s) encircles \(- 1 + j0\)
A.	once in clockwise direction
B.	twice in clockwise direction
C.	once in anticlockwise direction
D.	twice in anticlockwise direction
Answer» B. twice in clockwise direction

Discussion

5.	In the Bode plot of a unity feedback control system, the value of phase angle of G (jω) is -90° at the gain cross over frequency of the Bode plot, the phase margin of the system is:
A.	-180°
B.	+180°
C.	-90°
D.	+90°
Answer» E.

Discussion

6.	Consider two control systems with the following transfer functionsSystem 1: \(G\left( s \right) = \frac{1}{{3s + 1}}\) System 2: \(G\left( s \right) = \frac{1}{{s + 1}}\) Which of the following is true?
A.	Bandwidth of System 1 is greater than bandwidth of System 2
B.	Bandwidth of System 2 is greater than bandwidth of System 1
C.	Bandwidth of both the systems are same
D.	Both the systems have infinite bandwidth
Answer» C. Bandwidth of both the systems are same

Discussion

7.	If the gain of an open loop system is doubled, the gain margin
A.	Is not affected
B.	Gets double
C.	Becomes half
D.	Becomes one-fourth
Answer» D. Becomes one-fourth

Discussion

8.	For the transfer function, \(G\left( s \right) = \frac{{5\left( {s + 4} \right)}}{{s\left( {s + 0.25} \right)\left( {{s^2} + 10s + 25} \right)}}\), the values of the constant gain term and the highest corner frequency of the Bode plot respectively are:
A.	3.2, 5.0
B.	16.0, 4.0
C.	3.2, 4.0
D.	16.0, 5.0
Answer» B. 16.0, 4.0

Discussion

9.	Polar plot of sinusoidal transfer function is a plot of:
A.	magnitude and phase angle
B.	magnitude versus frequency
C.	phase angle versus frequency
D.	none of the above
Answer» B. magnitude versus frequency

Discussion

10.	If the gain margin of a system in decibels is negative, the system is:
A.	Stable
B.	Marginally stable
C.	Unstable
D.	Could be stable or unstable or marginally stable
Answer» D. Could be stable or unstable or marginally stable

Discussion

11.	Gain cross over frequency is that frequency at which _______
A.	\|GH(jω)\| = 0
B.	\|GH(jω)\| = 1
C.	\|GH(jω)\| = ∞
D.	\|GH(jω)\| = 1/√2
Answer» C. \|GH(jω)\| = ∞

Discussion

12.	______indicates not only whether a system is stable, but also its degree of stability and how stability may be imposed if necessary.
A.	Bode Plot
B.	Polar Plot
C.	Nyquist Plot
D.	Nichols Plot
Answer» D. Nichols Plot

Discussion

13.	Assertion (A): The stability analysis of systems with dead time can be conducted easily using the Bode plots.Reason (R): The magnitude plot of a system is unaffected by the presence of dead time.
A.	Both (A) and (R) are true and (R) is the correct explanation of (A).
B.	Both (A) and (R) are true, but (R) is not the correct explanation of (A).
C.	(A) is true, but (R) is false.
D.	(A) is false, but (R) is true.
Answer» B. Both (A) and (R) are true, but (R) is not the correct explanation of (A).

Discussion

14.	An all pass network imparts only
A.	Negative phase to the input
B.	Positive phase to the input
C.	+/–90 degree phase shift to the input
D.	+/–180 degree phase shift to the input
Answer» E.

Discussion

15.	If the period of a signal is 1000 ms, then what is its frequency in kilohertz?
A.	1 kHz
B.	10-2 kHz
C.	10-3 kHz
D.	10-1 kHz
Answer» D. 10-1 kHz

Discussion

16.	In time domain, the relative stability is measured by maximum overshoot and damping ratio. In frequency domain, the relative stability is measured by
A.	Steady state error
B.	Damping ratio
C.	Resonant peak
D.	Bandwidth
Answer» D. Bandwidth

Discussion

17.	A second-order system has\(\frac{C(s)}{R(s)}=\frac{ω_n^2}{(s^2+2ξω_n s+ω_n^2 )}\)Its frequency response will have a maximum value at the frequency:
A.	\(ω_n \sqrt{(1-ξ^2 )}\)
B.	ωnξ
C.	\(ω_n \sqrt{(1-2ξ^2 )}\)
D.	Zero
Answer» D. Zero

Discussion

18.	Gain margin is the factor by which gain of the system can be increased to make it:
A.	Stable
B.	Unstable
C.	Oscillatory
D.	Damped
Answer» C. Oscillatory

Discussion

19.	A family of constant N circles has the centre as
A.	X = 1 and Y = 2 N
B.	\(X=-\dfrac{1}{4} \ \text{and} \ Y = 4 \ N\)
C.	\(X=-\dfrac{1}{2} \ \text{and} \ Y=\dfrac{1}{4N}\)
D.	\(X=-\dfrac{1}{2} \ \text{and} \ Y=\dfrac{1}{2N}\)
Answer» E.

Discussion

20.	For a unity feedback system with open-loop transfer function, \(\frac{25}{s(s+6)}\) the resonant peak output M0 and the corresponding resonant frequency ωm are, respectively
A.	2.6 and 2.67 r/s
B.	1.04 and 2.67 r/s
C.	2.6 and 4.8 r/s
D.	1.04 and 4.8 r/s
Answer» C. 2.6 and 4.8 r/s

Discussion

21.	Consider the transfer function:\(G(s)=\frac{5(s^2+10s+100)}{s^2 (s^2+15s+1)}\)The corner frequencies in Bode’s plot for this transfer function are as
A.	10 r/s and 10 r/s
B.	100 r/s and 10 r/s
C.	10 r/s and 1 r/s
D.	100 r/s and 1 r/s
Answer» D. 100 r/s and 1 r/s

Discussion

22.	Consider the following statements:For an open-loop stable system, the Gain margin and Phase margin of the closed-loop system to make the closed-loop system unstable respectively are1. Positive, negative2. Negative, positive3. Negative, negativeWhich of the above statements is/are correct?
A.	3 only
B.	1 and 2 only
C.	2 and 3 only
D.	1, 2 and 3
Answer» E.

Discussion

23.	In a control system, the bandwidth of a system roughly measures:
A.	Phase crossover frequency
B.	Undamped natural frequency
C.	Resonant frequency
D.	Gain crossover frequency
Answer» E.

Discussion

24.	In a Bode magnitude plot, which one of the following slopes would be exhibited at high frequencies by a 4th order all-pole system –
A.	-80 dB/dec
B.	-40 dB/dec
C.	+40 dB/dec
D.	+80 dB/dec
Answer» B. -40 dB/dec

Discussion

25.	Calculate the gain margin of the system G(s) with unity feedback. Where G(s) is given as \(G\left( s \right) = \frac{5}{{s\left( {s + 5} \right)\left( {s + 15} \right)}}\)
A.	\(20{\log _{10}}500dB\)
B.	\(20{\log _{10}}300dB\)
C.	\(20{\log _{10}}50dB\)
D.	\(20{\log _{10}}100dB\)
Answer» C. \(20{\log _{10}}50dB\)

Discussion

26.	. Match the following Lists:List - IList - II1) (i) Stable but oscillatory system2) (ii) Stable and well-damped system3) (iii) Unstable system4) (iv) Marginally unstable system Correct codes are:
A.	a-ii, b-i, c-iv, d-iii
B.	a-ii, b-iii, c-i, d-iv
C.	a-iv, b-iii, c-i, d-ii
D.	a-iv, b-i, c-ii, d-iii
Answer» B. a-ii, b-iii, c-i, d-iv

Discussion

27.	A unity feedback control system is characterized by the open-loop transfer function\(G\left( s \right) = \frac{{10K\left( {s + 2} \right)}}{{{s^3} + 3{s^2} + 10}}\)The Nyquist path and the corresponding Nyquist plot of G(s) are shown in the figures below.If 0 < K < 1, then the number of poles of the closed-loop transfer function that lie in the right-half of the s-plane is
A.	0
B.	1
C.	2
D.	3
Answer» D. 3

Discussion

28.	A system with a unity gain margin and zero phase margin is ______
A.	Sluggish
B.	highly stable
C.	oscillatory
D.	relatively stable
Answer» D. relatively stable

Discussion

29.	A single-input single-output feedback system has forward transfer function G(s) and feedback transfer function H(s). It is given that \|G(s)H(s)\| < 1. Which of the following is true about the stability of the system?
A.	The system is always stable
B.	The system is stable if all zeros of G(s)H(s) are in left half of the s-plane
C.	The system is stable if all poles of G(s)H(s) are in left half of the s-plane
D.	It is not possible to say whether or not the system is stable from the information given
Answer» D. It is not possible to say whether or not the system is stable from the information given

Discussion

30.	If the gain of the open-loop system is doubled, the gain margin:
A.	Is not affected
B.	Gets doubled
C.	Becomes half
D.	Becomes one-fourth
Answer» D. Becomes one-fourth

Discussion

31.	A network has a pole at s = -1 and a zero at s = -2. If this network is excited by sinusoidal input, the output
A.	leads the input
B.	lags the input
C.	is in phase input
D.	decays exponentially to zero
Answer» C. is in phase input

Discussion

32.	A unity feedback system has the following open loop frequency response:ω (rad/sec)23456810\|G(jω)\|7.54.83.152.251.701.000.64∠G(jω)-118°-130°-140°-150°-157°-170°-180° The gain and phase margin of the system are
A.	0 dB, -180°
B.	3.88 dB, -170°
C.	0 dB, 10°
D.	3.88 dB, 10°
Answer» E.

Discussion

33.	Band width is the range of frequencies for which system gain is
A.	Less than 9 dB
B.	More than 20 dB
C.	More than -3 dB
D.	Less than 10 dB
Answer» E.

Discussion

34.	Consider the following1. Bode plot2. Nyquist plot3. Nichols chartWhich of the above frequency response plots are commonly employed in the analysis of control systems?
A.	1 and 2 only
B.	1 and 3 only
C.	2 and 3 only
D.	1, 2 and 3
Answer» E.

Discussion

35.	An op-amp based programmable gain amplifier with a negative feedback is designed. Which method will be the best suitable for the stability analysis?
A.	Bode Plot
B.	Nyquist Plot
C.	Root Locus
D.	R-H Stability Criteria
Answer» B. Nyquist Plot

Discussion

36.	Consider the following asymptotic Bode magnitude plot ( \(\omega\) is in rad/s).Which one of the following transfer functions is best represented by the above Bode magnitude plot?
A.	\(\frac{{2s}}{{\left( {1 + 0.5s} \right){{\left( {1 + 0.25s} \right)}^2}}}\)
B.	\(\frac{{4\left( {1 + 0.5s} \right)}}{{s\left( {1 + 0.25s} \right)}}\)
C.	\(\frac{{2s}}{{\left( {1 + 2s} \right)\left( {1 + 4s} \right)}}\)
D.	\(\frac{{4s}}{{\left( {1 + 2s} \right){{\left( {1 + 4s} \right)}^2}}}\)
Answer» B. \(\frac{{4\left( {1 + 0.5s} \right)}}{{s\left( {1 + 0.25s} \right)}}\)

Discussion

37.	Consider the sinusoidal transfer function in time-constant form\(G\left( {j\omega } \right) = \frac{{2\left( {1 + j\omega } \right)}}{{{{\left( {1 + \frac{{j\omega }}{{10}}} \right)}^2}}}\;\)Asymptotic log magnitude characteristic of factor (1 + jω) is a straight line of1. 0 dB for ω ≤ 1.2. + 20 dB/decade for ω ≥ 1.3. - 20 dB/decade for ω ≥ 1.Which of the above relations is/are correct?
A.	1 only
B.	1 and 2 only
C.	1 and 3 only
D.	2 only
Answer» C. 1 and 3 only

Discussion

38.	In a feedback control system, phase margin (PM) is:1. Directly proportional to ξ2. Inversely proportional to ξ3. Independent of ξ4. Zero when ξ = 0Which of the above statements are correct?
A.	1 and 2
B.	2 and 3
C.	3 and 4
D.	1 and 4
Answer» E.

Discussion

39.	If the given system is connected to a unity negative feedback system, the steady-state error of a closed-loop system to a ramp input is;
A.	0.01
B.	1
C.	0.5
D.	0.2
Answer» D. 0.2

Discussion

40.	For the Bode plot of the system\(G(s)=\frac{10}{0.66s^2+2.33s+1}\) the corner frequencies are:
A.	0.66 and 0.33
B.	0.22 and 2.00
C.	0.30 and 2.33
D.	0.50 and 3.00
Answer» E.

Discussion

41.	In bode plot, systems with dead time
A.	Introduces phase angle of \(\frac{{ - \omega {\tau _d} \times 180^\circ }}{\pi }\) in phase plot
B.	Introduces phase angle of \(\frac{{\omega {\tau _d} \times 180^\circ }}{\pi }\) in phase plot
C.	Introduces phase angle of \(\frac{{\omega {\tau _d}}}{\pi }\) in phase plot
D.	Phase plot is unaffected
Answer» B. Introduces phase angle of \(\frac{{\omega {\tau _d} \times 180^\circ }}{\pi }\) in phase plot

Discussion

42.	A transfer function having all its poles and zeroes only in the left half of the s-plane is called
A.	a minimum-phase transfer function
B.	a complex transfer function
C.	an all-pass transfer function
D.	a maximum-phase transfer function
Answer» B. a complex transfer function

Discussion

43.	In control systems, excessive bandwidth is NOT employed because:
A.	noise is proportional to bandwidth
B.	it leads to low relative stability
C.	it leads to slower response
D.	noise is proportional to the square of the bandwidth
Answer» B. it leads to low relative stability

Discussion

44.	Consider a unity feedback system having an open loop transfer function\(G(j\omega ) = \frac{k}{{j\omega \left( {j0.2\omega + 1} \right)\left( {j0.05\omega + 1} \right)}}\)Find open loop gain (k) with gain margin of 20 dB
A.	5.2
B.	2.5
C.	0.1
D.	2.25
Answer» C. 0.1

Discussion

45.	Phase margin of a system is used to specify
A.	Relative stability
B.	Absolute stability
C.	Time response
D.	Frequency response
Answer» B. Absolute stability

Discussion

46.	By adding a pole at the origin of s-plane, the Nyquist plot of a system will rotate by
A.	90° in anti-clockwise direction
B.	90° in clockwise direction
C.	180° in anti-clockwise direction
D.	180° in clockwise direction
Answer» C. 180° in anti-clockwise direction

Discussion

47.	If gain margin is close to unity or phase margin is close to zero, then the system is
A.	Highly stable
B.	Relatively stable
C.	Oscillatory
D.	Unstable
Answer» D. Unstable

Discussion

48.	A transfer function G(s) with the degree of its numerator polynomial zero and the degree of its denominator polynomial two has a Nyquist plot shown in the figure. The transfer function represents
A.	a stable, type-0 system
B.	a stable, type-1 system
C.	an unstable, type-0 system
D.	an unstable, type-1 system
Answer» E.

Discussion

49.	Directions: It consists of two statements, one labelled as the ‘Statement (I)’ and the other as ‘Statement (II)’. Examine these two statements carefully and select the answers to these items using the codes given below:Statement (I):The polar plot has limitation for portraying the frequency response of a system.Statement (II):The calculation of frequency response is tedious and does not indicate the effect of the individual poles and zeros.
A.	Both Statement (I) and Statement (II) are individually true and Statement (II) is the correct explanation of Statement (I)
B.	Both Statement (I) and Statement (II) are individually true but Statement (II) is not the correct explanation of Statement (I)
C.	Statement (I) is true but Statement (II) is false
D.	Statement (I) is false but Statement (II) is true
Answer» E.

Discussion

50.	A transfer function has its zeros in the right half of the s plane. The function
A.	is positive real
B.	is minimum phase
C.	will give stable impulse response
D.	is non-minimum phase
Answer» E.

Discussion

Explore topic-wise MCQs in Electronic Devices Circuits.

Nichol’s chart:

Which one of the following statements is correct?Nichol’s chart is useful for the detailed study of:

A system has fourteen poles and two zeros. Its high frequency asymptote in its magnitude plot having a slope of

Loop transfer function of a feedback system is \(G\left( s \right)H\left( s \right) = \frac{{s + 3}}{{{s^2}\left( {s - 3} \right)}}\;.\) Take the Nyquist contour in the clockwise direction. Then, the Nyquist plot of G(s) H(s) encircles \(- 1 + j0\)

In the Bode plot of a unity feedback control system, the value of phase angle of G (jω) is -90° at the gain cross over frequency of the Bode plot, the phase margin of the system is:

Consider two control systems with the following transfer functionsSystem 1: \(G\left( s \right) = \frac{1}{{3s + 1}}\) System 2: \(G\left( s \right) = \frac{1}{{s + 1}}\) Which of the following is true?

If the gain of an open loop system is doubled, the gain margin

For the transfer function, \(G\left( s \right) = \frac{{5\left( {s + 4} \right)}}{{s\left( {s + 0.25} \right)\left( {{s^2} + 10s + 25} \right)}}\), the values of the constant gain term and the highest corner frequency of the Bode plot respectively are:

Polar plot of sinusoidal transfer function is a plot of:

If the gain margin of a system in decibels is negative, the system is:

Gain cross over frequency is that frequency at which _______

______indicates not only whether a system is stable, but also its degree of stability and how stability may be imposed if necessary.

Assertion (A): The stability analysis of systems with dead time can be conducted easily using the Bode plots.Reason (R): The magnitude plot of a system is unaffected by the presence of dead time.

An all pass network imparts only

If the period of a signal is 1000 ms, then what is its frequency in kilohertz?

In time domain, the relative stability is measured by maximum overshoot and damping ratio. In frequency domain, the relative stability is measured by

A second-order system has\(\frac{C(s)}{R(s)}=\frac{ω_n^2}{(s^2+2ξω_n s+ω_n^2 )}\)Its frequency response will have a maximum value at the frequency:

Gain margin is the factor by which gain of the system can be increased to make it:

A family of constant N circles has the centre as

For a unity feedback system with open-loop transfer function, \(\frac{25}{s(s+6)}\) the resonant peak output M0 and the corresponding resonant frequency ωm are, respectively

Consider the transfer function:\(G(s)=\frac{5(s^2+10s+100)}{s^2 (s^2+15s+1)}\)The corner frequencies in Bode’s plot for this transfer function are as

Consider the following statements:For an open-loop stable system, the Gain margin and Phase margin of the closed-loop system to make the closed-loop system unstable respectively are1. Positive, negative2. Negative, positive3. Negative, negativeWhich of the above statements is/are correct?

In a control system, the bandwidth of a system roughly measures:

In a Bode magnitude plot, which one of the following slopes would be exhibited at high frequencies by a 4th order all-pole system –

Calculate the gain margin of the system G(s) with unity feedback. Where G(s) is given as \(G\left( s \right) = \frac{5}{{s\left( {s + 5} \right)\left( {s + 15} \right)}}\)

. Match the following Lists:List - IList - II1) (i) Stable but oscillatory system2) (ii) Stable and well-damped system3) (iii) Unstable system4) (iv) Marginally unstable system Correct codes are:

A system with a unity gain margin and zero phase margin is ______

A single-input single-output feedback system has forward transfer function G(s) and feedback transfer function H(s). It is given that |G(s)H(s)| < 1. Which of the following is true about the stability of the system?

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

A network has a pole at s = -1 and a zero at s = -2. If this network is excited by sinusoidal input, the output

A unity feedback system has the following open loop frequency response:ω (rad/sec)23456810|G(jω)|7.54.83.152.251.701.000.64∠G(jω)-118°-130°-140°-150°-157°-170°-180° The gain and phase margin of the system are

Band width is the range of frequencies for which system gain is

Consider the following1. Bode plot2. Nyquist plot3. Nichols chartWhich of the above frequency response plots are commonly employed in the analysis of control systems?

An op-amp based programmable gain amplifier with a negative feedback is designed. Which method will be the best suitable for the stability analysis?

Consider the following asymptotic Bode magnitude plot ( \(\omega\) is in rad/s).Which one of the following transfer functions is best represented by the above Bode magnitude plot?

In a feedback control system, phase margin (PM) is:1. Directly proportional to ξ2. Inversely proportional to ξ3. Independent of ξ4. Zero when ξ = 0Which of the above statements are correct?

If the given system is connected to a unity negative feedback system, the steady-state error of a closed-loop system to a ramp input is;

For the Bode plot of the system\(G(s)=\frac{10}{0.66s^2+2.33s+1}\) the corner frequencies are:

In bode plot, systems with dead time

A transfer function having all its poles and zeroes only in the left half of the s-plane is called

In control systems, excessive bandwidth is NOT employed because:

Consider a unity feedback system having an open loop transfer function\(G(j\omega ) = \frac{k}{{j\omega \left( {j0.2\omega + 1} \right)\left( {j0.05\omega + 1} \right)}}\)Find open loop gain (k) with gain margin of 20 dB

Phase margin of a system is used to specify

By adding a pole at the origin of s-plane, the Nyquist plot of a system will rotate by

If gain margin is close to unity or phase margin is close to zero, then the system is

A transfer function G(s) with the degree of its numerator polynomial zero and the degree of its denominator polynomial two has a Nyquist plot shown in the figure. The transfer function represents

A transfer function has its zeros in the right half of the s plane. The function