Question

In the circuit shown below, find the Z-parameter Z12.

(a) 15

(b) 10

(c) 5

(d) 1

I have been asked this question in an online interview.

This is a very interesting question from Inter Connection of Two-Port Networks in section Two-Port Networks of Network Theory

Answer 1

The correct answer is (c) 5

To explain I would say: The Z-parameter Z12 is V2/I1 |I2=0. On open circuiting port 2 we obtain the equation, V1 = (5) I2 => V1/I1 = 5. On substituting we get Z12 = 5Ω.