gaus12777 Messages 12 Reaction score 1 Thread starter Dec 4, 2016 #1 Could you tell me the reason that if pole is close to the imaginary axis, (1) can be same as (2).
FactChecker Science Advisor Homework Helper Messages 9,545 Reaction score 4,786 Dec 5, 2016 #2 The fact that the roots of (1) are close to the imaginary axis tells you (from the real part of the quadratic equation) that 2ζpωp is small. Ignoring that part of (1) gives (2).
The fact that the roots of (1) are close to the imaginary axis tells you (from the real part of the quadratic equation) that 2ζpωp is small. Ignoring that part of (1) gives (2).