Question

In two-port networks the parameter g21 is called _________

(a) Short circuit input impedance

(b) Short circuit current ratio

(c) Open circuit  voltage ratio

(d) Open circuit input admittance

I had been asked this question in an interview.

This intriguing question comes from Inverse Hybrid (g) Parameter topic in portion Two-Port Networks of Network Theory

Answer 1

Right option is (c) Open circuit  voltage ratio

For explanation I would say: We know that, g21 = $\frac{V_2}{V_1}$, when I2 = 0.

Since the second output terminal is short circuited when the ratio of the two voltages is measured, therefore the parameter g21 is called as Open circuit voltage ratio.