Question

The gain margin of a unity feedback control system with the open loop transfer function is
$G\left(s\right)=\frac{(s+1)}{s^2}$

• A. 0
• B. $\frac{1}{\sqrt{2}}$
• C. $\sqrt{2}$
• D. $\infty$

Answer 1

The correct option is D $\infty$



$-1+j0$ is not enclosed, system is always stable.
$\therefore G.M=\infty$