Automatic Control Systems - Engineering

Q1:

If poles lie in first quadrant, damping ratio is

A 1

B more than 1

C less than 1

D zero

ANS:C - less than 1

The pole in first quadrant means poles are positive and real so let us take an example
transfer function 1/(s-2)(s-5).

So characteristic equation of this function is s^2-10s+10=0

So Wn = √(10) and damping factor =-10/2* √(10) the value of this is Negative so less than 1 is the correct one.