A unity feedback system as shown has damping ratio of 0.8 using derivative control

Following parameter are obtained

(A) Characteristic equation is s² + 1.6s + 16 = 0

(B) ξ = 0.2 (without derivative control)

(C) ξ = 0.8 (without derivative control)

(D) ω_n = 4 rad/sec

Choose the most appropriate answer from the options given below:

(1) (A), (C) and (D) only

(2) (B), (D) only

(3) (A), (B), (D) only

(4) (C), (D)

Question

Question

This question was previously asked in

UGC NET Paper 2: Electronic Science Nov 2020 Official Paper

Answer 1

F28 Shubham B 5-4-2021 Swati D1

(A) Characteristic Equation ⇒ 1 + GH(s) = 0

\(1 + \frac{{16}}{{{s^2} + 1.6s}} = 0\)

s² + 1.6s + 16 = 0

(B) 2ξ ω_n = 1.6

& \(\omega _n^2 = 16\)

ω_n = 4

2 × ξ × 4 = 1.6

\(\xi = \frac{{1.6}}{8} = 0.2\)

(C) Statement C is wrong

(D) ω_n = 4 rad/sec

Statement A, B & D are correct

Option (3) is correct