Explore topic-wise MCQs in Control Systems.

This section includes 19 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.

In closed loop control system, what is the sensitivity of the gain of the overall system, M to the variation in G?

A. 1/1+GH
B. 1/1+G
C. G/1GH
D. G/1+G
Answer» B. 1/1+G
Discussion
2.

Phase margin is always positive for stable feedback system?

A. True
B. False
Answer» B. False
Discussion
3.

How many roots with positive real parts do the equation s3+s2-s+1=0 have?

A. 0
B. 1
C. 2
D. 3
Answer» D. 3
Discussion
4.

For what values of K does the polynomial s4+8s3+24s2+32s+K=0 have roots with zero real parts?

A. 10
B. 20
C. 40
D. 80
Answer» E.
Discussion
5.

Which of the following may result in instability problem?

A. Large error
B. High selectivity
C. High gain
D. Noise
Answer» D. Noise
Discussion
6.

The characteristic equation of a control system is given by s5+s4+2s3+2s2+4s+6=0. The number of the roots of the equation which lie on the right half of s-plane:

A. 0
B. 1
C. 2
D. 3
Answer» D. 3
Discussion
7.

The characteristic equation of a system is 2s5+s4+4s3+2s2+2s+1=0 . Which one of the following is correct?

A. Stable
B. Marginally stable
C. Unstable
D. Oscillatory
Answer» D. Oscillatory
Discussion
8.

The characteristic equation of the control system is s5+15s4+85s3+225s2+274s+120=0 . What are the number of roots of the equation which lie to the left of the line s+1 = 0?

A. 2
B. 3
C. 4
D. 5
Answer» D. 5
Discussion
9.

The open loop control transfer function of a unity feedback system is given by :G(s) =K/(s+2)(s+4)(s^2+6s+25)Which is the value of K which causes sustained oscillations in the closed loop system?

A. 590
B. 790
C. 990
D. 1190
Answer» B. 790
Discussion
10.

Assertion (A): The closed loop stability can be determined from the poles of an open loop system and the polar plot of the frequency response.Reason (R): Unstable system has right half poles.

A. Both A and R are true and R is correct explanation of A
B. Both A and R are true and R is not correct Explanation of A
C. A is True and R is false
D. A is False and R is true
Answer» C. A is True and R is false
Discussion
11.

PHASE_MARGIN_IS_ALWAYS_POSITIVE_FOR_STABLE_FEEDBACK_SYSTEM??$

A. True
B. False
Answer» B. False
Discussion
12.

In closed loop control system, what is the sensitivity of the gain of the overall system, M to the variation in G?$

A. 1/1+GH
B. 1/1+G
C. G/1GH
D. G/1+G
Answer» B. 1/1+G
Discussion
13.

How many roots with positive real parts do the equation s3+s2-s+1=0 have?

A. 0
B. 1
C. 2
D. 3
Answer» D. 3
Discussion
14.

For what values of K does the polynomial s4+8s3+24s2+32s+K=0 have roots with zero real parts?

A. 10
B. 20
C. 40
D. 80
Answer» E.
Discussion
15.

The characteristic equation of a control system is given by s5+s4+2s3+2s2+4s+6=0. The number of the roots of the equation which lie on the right half of s-plane:

A. 0
B. 1
C. 2
D. 3
Answer» D. 3
Discussion
16.

The characteristic equation of a system is 2s5+s4+4s3+2s2+2s+1=0 . Which one of the following is correct?

A. Stable
B. Marginally stable
C. Unstable
D. Oscillatory
Answer» D. Oscillatory
Discussion
17.

The characteristic equation of the control system is s5+15s4+85s3+225s2+274s+120=0 . What are the number of roots of the equation which lie to the left of the line s+1 = 0?

A. 2
B. 3
C. 4
D. 5
Answer» D. 5
Discussion
18.

The open loop control transfer function of a unity feedback system is given by :

A. =K/(s+2)(s+4)(s^2+6s+25)
B.
C. 590
Answer» B.
Discussion
19.

Assertion (A): The closed loop stability can be determined from the poles of an open loop system and the polar plot of the frequency response.

A. : Unstable system has right half poles.
B. Both A and R are true and R is correct explanation of A
C. Both A and R are true and R is not correct Explanation of A
D. A is True and R is false
Answer» C. Both A and R are true and R is not correct Explanation of A
Discussion