Question

The poles of driving point impedance are those frequencies corresponding to ___________ conditions.

(a) short circuit

(b) voltage source

(c) open circuit

(d) current source

I had been asked this question in class test.

The above asked question is from Properties of Driving Point Functions topic in chapter S-Domain Analysis of Network Theory

Answer 1

Correct answer is (c) open circuit

To elaborate: A zero of N(s) is a zero of V(s), it signifies a short circuit. Similarly, a pole of Z(s) is a zero of I(s). The poles of driving point impedance are those frequencies corresponding to open circuit conditions.