Related InterviewSolutions

• Consider a negative feedback system where G(s) =1/(s+1) and H(s) =K/s(s+2). The closed loop system is stable for(a) K>6(b) 0
• Consider a characteristic equation, s^4+3s^3+5s^2+6s+k+10=0. The condition for stability is(a) K>5(b) -10-4(d) -10
• A system with unity feedback having open loop transfer function as G(s) = K(s+1)/s3+as2+2s+1. What values of ‘K’ and ’a’ should be chosen so that the system oscillates ?(a) K =2, a =1(b) K =2, a =0.75(c) K =4, a =1(d) K =4, a =0.75I had been asked this question during an online exam.My question is taken from Relative Stability Analysis in portion Stability and Algebraic Criteria of Control Systems
• The necessary condition for the stability of the linear system is that all the coefficients of characteristic equation 1+G(s)H(s) =0, be real and have the :(a) Positive sign(b) Negative sign(c) Same sign(d) Both positive and negativeI have been asked this question in an online interview.My question is from Routh-Hurwitz Stability Criterion topic in chapter Stability and Algebraic Criteria of Control Systems
• Determine the value of K such that roots of characteristic equation given below lies to the left of the line s = -1. s^3+10s^2+18s+K.(a) K>16 and K
• Consider the following statement:(a) A system is said to be stable if its output is bounded for any input(b) A system is said to be stable if all the roots of the characteristic equation lie on the left half of the s plane.(c) A system is said to be stable if all the roots of the characteristic equation have negative real parts.(d) A second order system is always stable for finite values of open loop gainThe question was asked in an online interview.Query is from Routh-Hurwitz Stability Criterion in division Stability and Algebraic Criteria of Control Systems
• The characteristic equation of a feedback control system is s^3+Ks^2+9s+18. When the system is marginally stable, the frequency of the sustained oscillation:(a) 1(b) 1.414(c) 1.732(d) 3This question was posed to me by my school teacher while I was bunking the class.My doubt stems from Relative Stability Analysis in portion Stability and Algebraic Criteria of Control Systems
• The polynomial s^4+Ks^3+s^2+s+1=0 the range of K for stability is _____________(a) K>5(b) -10-4(d) K-1>0This question was posed to me in unit test.Query is from Relative Stability Analysis topic in division Stability and Algebraic Criteria of Control Systems
• The characteristic equation of a system is given ass3+25s2+10s+50=0. What is the number of the roots in the right half s-plane and the imaginary axis respectively?(a) 1,1(b) 0,0(c) 2,1(d) 1,2The question was posed to me in unit test.Origin of the question is Routh-Hurwitz Stability Criterion topic in chapter Stability and Algebraic Criteria of Control Systems
• Consider the following statement regarding Routh Hurwitz criterion:(a) It gives absolute stability(b) It gives gain and phase margin(c) It gives the number of roots lying in RHS of the s-plane(d) It gives gain, phase margin and number of roots lying in RHS of the s-planeI have been asked this question in an online interview.I need to ask this question from Routh-Hurwitz Stability Criterion topic in chapter Stability and Algebraic Criteria of Control Systems