Explore topic-wise MCQs in Control Systems.

This section includes 16 Mcqs, each offering curated multiple-choice questions to sharpen your Control Systems knowledge and support exam preparation. Choose a topic below to get started.

1.

Phase margin is:

A. It is amount of additional phase lag at the gain cross over frequency required to bring the system to the verge of instability
B. It is always positive for stable feedback systems
C. It is calculated at gain cross over frequency
D. All of the mentioned
Answer» E.
2.

Gain margin is:

A. It is a factor by which the system gain can be increased to drive it to the verge of instability
B. It is calculated at gain cross over frequency
C. It is calculated at phase cross over frequency
D. Both a and c
Answer» E.
3.

Phase and gain margin are applicable to open and closed loop systems both.

A. True
B. False
Answer» C.
4.

The phase angle of the system, G(s) =s+5/s2+4s+9, varies between :

A. 0° and 90°
B. 0° and -90°
C. 0° and -180°
D. -90° and -180°
Answer» B. 0° and -90°
5.

The system with the open loop transfer function G(s) H(s) =1/s(s^2+s+1) has the gain margin of :

A. -6 dB
B. 0 dB
C. 3.5 dB
D. 6 dB
Answer» C. 3.5 dB
6.

The phase margin (in degrees) of a system having the loop transfer function G(s) H(s)=2√3/s(s+1) is:

A. 45°
B. -30°
C. 60°
D. 30°
Answer» E.
7.

GAIN_MARGIN_IS:?$

A. It is a factor by which the system gain can be increased to drive it to the verge of instability
B. It is calculated at gain cross over frequency
C. It is calculated at phase cross over frequency
D. Both a and c
Answer» E.
8.

Phase margin is:$

A. It is amount of additional phase lag at the gain cross over frequency required to bring the system to the verge of instability
B. It is always positive for stable feedback systems
C. It is calculated at gain cross over frequency
D. All of the mentioned
Answer» E.
9.

Phase and gain margin are applicable to open and closed loop systems both?

A. True
B. False
Answer» C.
10.

The concepts used to measure relative stability are:

A. Phase margin
B. Gain margin
C. Phase and Gain margin
D. Stable
Answer» D. Stable
11.

Polar plots moving toward the imaginary axis makes the system:

A. Stable
B. Marginally stable
C. Conditionally stable
D. Unstable
Answer» E.
12.

As the polar plot moves toward the point (-1, 0) then the system becomes :

A. Stable
B. Marginally stable
C. Conditionally stable
D. Unstable
Answer» E.
13.

The polar plot of the transfer function G(s) = 10(s+1)/s+10 will be in the :

A. First quadrant
B. Second quadrant
C. Third quadrant
D. Fourth quadrant
Answer» E.
14.

The phase angle of the system, G(s) =s+5/s2+4s+9, varies between :

A. 0° and 90°
B. 0° and -90°
C. 0° and -180°
D. -90° and -180°
Answer» B. 0¬¨¬®‚Äö√†√ª and -90¬¨¬®‚Äö√†√ª
15.

The system with the open loop transfer function G(s) H(s) =1/s(s^2+s+1) has the gain margin of :

A. -6 dB
B. 0 dB
C. 3.5 dB
D. 6 dB
Answer» C. 3.5 dB
16.

The phase margin (in degrees) of a system having the loop transfer function G(s) H(s)=2‚àö3/s(s+1) is:

A. 45°
B. -30°
C. 60°
D. 30°
Answer» E.