Automatic Control Systems - Engineering

Q1:

For a second order system with 0 < ξ < 1, the angle which poles make with negative real axis is

A sin-1 ξ

B cos-1 ξ

C tan-1 ξ

D cot-1 ξ

ANS:B - cos-1 ξ

Yes, the right answer is B. Because cos theta = damping ration where thet is the angle which polar plot point makes with the postive real axis.