# GATE Questions & Answers of Bode and root-locus plots

## What is the Weightage of Bode and root-locus plots in GATE Exam?

Total 10 Questions have been asked from Bode and root-locus plots topic of Control Systems subject in previous GATE papers. Average marks 1.70.

The open-loop transfer function of a unity-feedback control system is

The value of K at the breakaway point of the feedback control system’s root-locus plot is ________

The forward-path transfer function and the feedback-path transfer function of a single loop negative feedback control system are given as

respectively. If the variable parameter K is real positive, then the location of the breakaway point on the root locus diagram of the system is __________

A unity negative feedback system has the open-loop transfer function $G\left(s\right)=\frac{K}{s\left(s+1\right)\left(s+3\right)}$. The value of the gain K (>0) at which the root locus crosses the imaginary axis is ______.

The open-loop transfer function of a plant in a unity feedback configuration is given as . The value of the gain K (>0) for which the point –1 + 2 lies on the root locus is _____.

For the system shown in the figure, s=-2.75 lies on the root locus if K is__________

In the root locus plot shown in the figure, the pole/zero marks and the arrows have been removed. Which one of the following transfer functions has this root locus?

The Bode plot of a transfer function G(s) is shown in the figure below.

The gain is 32 dB and -8 dB at 1 rad/s and 10 rad/s respectively. The phase is negative for all ω. Then G(s) is

The root locus plot for a system is given below. The open loop transfer function corresponding to this plot is given by

The feedback configuration and the pole-zero locations of $G\left(s\right)=\frac{{s}^{2}-2s+2}{{s}^{2}+2s+2}$ are shown below. The root locus for negative values of k, i.e. for −$\infty$ < k < 0, has breakaway/break in points and angle of departure at pole P (with respect to the positive real axis) equal to
A unity feedback control system has an open-loop transfer function $G\left(s\right)=\frac{K}{s\left({s}^{2}+7s+12\right)}$. The gain K for which s = -1 + j1 will lie on the root locus of this system is