Question

The relation between Z21 and Y parameters is?

(a) Z21 = Y21/∆y

(b) Z21 = Y12/∆y

(c) Z21 = (-Y21)/∆y

(d) Z21 = (-Y12)/∆y

The question was asked in quiz.

Origin of the question is Inner Relationships of Different Parameters topic in division Two-Port Networks of Network Theory

Answer 1

Right choice is (c) Z21 = (-Y21)/∆y

For explanation: V2=(-Y21/∆y)I1+(Y11/∆y)I2. The relation between Z21 and Y parameters is Z21 = (-Y21)/∆y.