Question

A driving point impedance with zero at ω = 0 and pole at ω = ∞ must have ___________ term in the numerator polynomial.

(a) s^1+ωn^1

(b) s^2+ωn^1

(c) s^1+ωn^2

(d) s^2+ωn^2

I have been asked this question by my college professor while I was bunking the class.

The origin of the question is Frequency Response of Reactive One-Ports in chapter Elements of Realizability and Synthesis of One-Port Networks of Network Theory

Answer 1

The correct choice is (d) s^2+ωn^2

For explanation I would say: If a pole is at ω = ∞, there will be an equal number of s^2+ωn^2 type terms in the numerator polynomial and the denominator polynomial.