Control Systems MCQ Questions & Answers

11

The Nyquist plot of: $$G\left( s \right).H\left( s \right) = \frac{{10}}{{{s^2}\left( {1 + 0.5s} \right).\left( {1 + s} \right)}}$$

A) will start (ω = ∞) in the first quadrant and will terminate (ω = 0) in the second quadrant B) will start (ω = ∞) in the fourth quadrant and will terminate (ω = 0) in the second quadrant C) will start (ω = ∞) in the second quadrant and will terminate (ω = 0) in the third quadrant D) will start (ω = ∞) in the first quadrant and will terminate (ω = 0) in the fourth quadrant

Discuss

Answer & Solution

Answer: Option A

No explanation is given for this question. Let's Discuss on Board

12

A phase lead compensating network has its transfer function $${G_C}\left( s \right) = \frac{{10\left( {1 + 0.04s} \right)}}{{\left( {1 + 0.01s} \right)}}.$$ The maximum phase lead occurs at a frequency of:

A) 50 rad/s B) 25 rad/s C) 10 rad/s D) 4 rad/s

Discuss

Answer & Solution

Answer: Option A

No explanation is given for this question. Let's Discuss on Board

13

Which one of the following compensation is adopted for improving transient response of a negative unity feedback system?

A) Phase lead compensation B) Phase lag compensation C) Gain compensation D) Both phase lag compensation and gain compensation

Discuss

Answer & Solution

Answer: Option A

No explanation is given for this question. Let's Discuss on Board

14

A liquid level controller linearly converts a displacement of 2 m to 3 m into 4-20 mA control signal. A relay serves as two position controller to open and close an inlet valve. Relay closes at 12 mA and opens at 10 mA. The hysteresis zone is:

A) 0.1 m B) 0.125 m C) 0.15 m D) 0.2 m

Discuss

Answer & Solution

Answer: Option B

No explanation is given for this question. Let's Discuss on Board

15

Given the system transfer function $$G\left( s \right) = \frac{{K{e^{ - 0.2s}}}}{{s\left( {s + 2} \right)\left( {s + 8} \right)}},$$ the corner frequencies in rad/s are

A) 0.2, 0.6 B) 1, 4 C) 3, 7 D) 2, 8

Discuss

Answer & Solution

Answer: Option D

No explanation is given for this question. Let's Discuss on Board

16

A second order LTI system is described by the following state equations
\[\frac{{\rm{d}}}{{{\rm{dt}}}}\] x₁(t) - x₂(t) = 0
\[\frac{{\rm{d}}}{{{\rm{dt}}}}\] x₂(t) + 2x₁(t) + 3x₂(t) = r(t) where x₁(t) and x₂(t) are the two state variables and r(t) denotes the input. The output c(t) = x₁(t).
The system is

A) undamped (oscillatory) B) underdamped C) critically damped D) overdamped

Discuss

Answer & Solution

Answer: Option D

No explanation is given for this question. Let's Discuss on Board

17

Where are the K = ±∞ points on the root loci of the characteristic equation of the closed loop control system located at?

A) Poles of G(s)H(s) B) Zeroes of G(s)H(s) C) Both Zeros and Poles of G(s)H(s) D) Neither at Zeros nor at Poles of G(s)H(s)

Discuss

Answer & Solution

Answer: Option B

No explanation is given for this question. Let's Discuss on Board

18

The feedback control system in the figure is stable.
Control Systems mcq question image

A) for all K ≥ 0 B) only if K ≥ 0 C) only if 0 ≤ K < 1 D) only if 0 ≤ K ≤ 2

Discuss

Answer & Solution

Answer: Option C

No explanation is given for this question. Let's Discuss on Board

19

Consider the characteristic equation of a control system given by s³ + (K + 0.5)s² + 4Ks + 50 = 0. Find the value of K for the system to have sustained oscillations.

A) 3.1 B) 3.8 C) 3.3 D) 4.3

Discuss

Answer & Solution

Answer: Option C

No explanation is given for this question. Let's Discuss on Board

20

The open-loop transfer function of a system is given by $$G\left( s \right)H\left( s \right) = \frac{{100\left( {s + 100} \right)}}{{s\left( {s + 10} \right)}}.$$ In the straight line approximation of the Bode plot, |G(jω) H(jω)| and ∠G(jω) H(jω) at ω = 100 rad/s are:

A) 0 dB and $$\frac{{ - 3\pi }}{4}$$ rad B) 0 dB and $$\frac{\pi }{4}$$ rad C) 20 dB and $$\frac{{ - 3\pi }}{4}$$ rad D) 20 dB and $$\frac{\pi }{4}$$ rad

Discuss

Answer & Solution

Answer: Option C

No explanation is given for this question. Let's Discuss on Board

Control Systems MCQ Questions & Answers | ECE