Direction: It consists of two statements, one labelled as Stateme
Direction: It consists of two statements, one labelled as Statement (I) and the other as Statement (II). Examine these two statements carefully and select the answers to these items using the codes given below:
Statement (I): Z parameters are known as open circuit impedance parameters.
Statement (II): Z parameters are represented by the equations: V1 = z11 I1 + z12 I2 and V2 = z21 I1 + z22 I2.
A. Both statement (I) and Statement (II) are individually true and Statement (II) is the correct explanation of Statement (I)
B. Both statement (I) and Statement (II) are individually true and Statement (II) is not the correct explanation of Statement (I)
C. Statement (I) is true but Statement (II) is false
D. Statement (I) is false but Statement (II) is true
Please scroll down to see the correct answer and solution guide.
Right Answer is: B
SOLUTION
Z-parameters:
Z-parameters are also known as the Open-Circuit impedance parameters as they are calculated under open-circuit conditions, i.e. at I1 = 0 and I2 = 0, In the matrix form, they are expressed as:
\(\left[ {\begin{array}{*{20}{c}} {{V_1}}\\ {{V_2}} \end{array}} \right] = \left[ {\begin{array}{*{20}{c}} {{z_{11}}}&{{z_{12}}}\\ {{z_{21}}}&{{z_{22}}} \end{array}} \right]\left[ {\begin{array}{*{20}{c}} {{I_1}}\\ {{I_2}} \end{array}} \right]\)
V1 = z11I1 + z12I2
V2 = z21I1 + z22I2
With the input open-circuited, i.e. I1 = 0, the two parameters obtained are:
\({z_{12}} = {\left. {\frac{{{V_1}}}{{{I_2}}}} \right|_{{I_1} = 0}}\)
\({z_{22}} = {\left. {\frac{{{V_2}}}{{{I_2}}}} \right|_{{I_1} = 0}}\)
With the output open-circuited, i.e. I2 = 0, the two parameters we obtain are:
\({z_{11}} = {\left. {\frac{{{V_1}}}{{{I_1}}}} \right|_{{I_2} = 0}}\)
\({z_{21}} = {\left. {\frac{{{V_2}}}{{{I_1}}}} \right|_{{I_2} = 0}}\)
Therefore, Both statement (I) and Statement (II) are individually true and Statement (II) is not the correct explanation of Statement (I)
|
Two-port network parameters |
Equations |
|
Z parameters |
V1 = Z11I1 + Z12I2 V2 = Z21I1 + Z22I2 |
|
Y parameters |
I1 = Y11V1 + Y12V2 I2 = Y21V1 + Y22V2 |
|
h parameters |
V1 = h11I1 + h12V2 I2 = h21I1 + h22V2 |
|
g parameters |
I1 = g11V1 + g12I2 V2 = g21V1 + g22I2 |
|
T parameters (ABCD) |
V1 = AV2 – BI2 I1 = CV2 – DI2 |
|
Inverse T parameters |
V2 = A’V1 – B’I1 I2 = C’V1 – D’I1 |
