1. The Z-matrix of a 2-port network is given by

$Z=\begin{bmatrix} 0.9 & 0.2\\ 0.2 & 0.6 \end{bmatrix}$

The element Y_{22} of the corresponding Y matrix of the same network is given by

- 1.2
- 0.4
- -0.4
- 1.8

2. A passive two-port network is in a steady state. Compared to its input, the steady-state output can never offer

- higher voltage
- lower impedance
- greater power
- better regulation

3. If a two-port network is reciprocal, then we have, with the usual notation, the following relationship

- h
_{12}= h_{21} - h
_{12}= -h_{21} - h
_{11}= h_{22} - h
_{11}h_{22}– h_{12}h_{21}= 1

4. A two-port device is defined by the following pair of equations:

i_{1} = 2v_{1} + v_{2} and i_{2} = v_{1} + v_{2}

Its impedance parameters $\begin{bmatrix} z_{11} & z_{12}\\ z_{21} & z_{22} \end{bmatrix}$ are given by

- $\begin{bmatrix} 2 & 1\\ 1 & 1 \end{bmatrix}$
- $\begin{bmatrix} 1 & -1\\ -1 & 2 \end{bmatrix}$
- $\begin{bmatrix} 1 & 1\\ 1 & 2 \end{bmatrix}$
- $\begin{bmatrix} 2 & -1\\ -1 & 1 \end{bmatrix}$

5. In a linear two-port network, when 10 V is applied to port 1, a current of 4 A flows through port 2 when it is short-circuited. When 5 V is applied to port 1, a current of 1.25 A flows through a 1 Ω resistance connected across port 2. When 3 V is applied to port 1, the current (in Ampere) through a 2 Ω resistance connected across port 2 is

- 0.545
- 0.490
- 0.360
- 0.708

6. Consider the following standard symbols for two-port parameters:

- h
_{12}and h_{21}are dimensionless - h
_{11}and B have dimensions of ohms - BC is dimensionless
- C is dimensionless

Which of the above are correct?

- i, ii and iii only
- i, ii and iv only
- iii and iv only
- i, ii, iii and iv

7. A 2-port network is represented by the following equations

V_{1} = 60I_{1} + 20I_{2}

V_{2} = 20I_{1} + 40I_{2}

The ABCD parameters of the above network would be

- $\begin{bmatrix} 2 & \frac{1}{20}\\ 3 & 100 \end{bmatrix}$
- $\begin{bmatrix} 100 & 3\\ 2 & \frac{1}{20} \end{bmatrix}$
- $\begin{bmatrix} 100 & 20\\ 6 & 3 \end{bmatrix}$
- $\begin{bmatrix} 3 & 100\\ \frac{1}{20} & 2 \end{bmatrix}$

8. The condition for reciprocity for a two-port transmission network is expressed by

- $\begin{vmatrix} A & B\\ C & D \end{vmatrix}=0$
- $\begin{vmatrix} A & D\\B & C \end{vmatrix}=1$
- $\begin{vmatrix} A & C\\ B & D \end{vmatrix}=0$
- $\begin{vmatrix} A & B\\ C & D \end{vmatrix}=1$

9. A 2-port network is defined by the relation,

$V_1=\frac{3}{4}I_1-\frac{1}{4}I_2\; , V_2=-\frac{1}{2}I_1+\frac{1}{2}I_2\;$

Then y_{12} is

- 0.5 mho
- -0.5 mho
- 1 mho
- -1 mho

10. A two-port network is described by the following equations

V_{1} = 50I_{1} + 20I_{2}

V_{2} = 30I_{1} + 10I_{2}

Then, which one of the following is not correct?

- Z
_{12}= 20 Ω - Y
_{12}= 0.2 mho - h
_{12}= 2 - A = 25

11. A two-port network is defined by the relation:

I_{1} = 5V_{1} + 3V_{2}

I_{2} = 2V_{1} – 7V_{2}

The value of z_{12} is

- 3 Ω
- -3 Ω
- 3/41 Ω
- 2/31 Ω

12. A, B, C and D represent the transmission parameters of a two-port network. When is the network reciprocal?

- AB – CD = 1
- AD – BC = 1
- AB – CD = 0
- AD – BC = 0

13. The h parameters h_{11} and h_{22} are related to z and y parameters as

- h
_{11}= z_{11}and h_{22}= 1/z_{22} - h
_{11}= z_{11}and h_{22}= y_{22} - h
_{11}= 1/y_{11}and h_{22}= 1/z_{22} - h
_{11}= 1/y_{11}and h_{22}= y_{22}

14. For a two-port symmetrical bilateral network, if transmission A = 2 and B = 1 ohm, then the value of parameter C is equal to

- 3 ohms
- 6 ohms
- 9 ohms
- 12 ohms

15. The two-port parameter h_{21} is called

- open-circuit output admittance
- short-circuit input impedance
- open-circuit reverse voltage gain
- short-circuit forward current gain

16. In a two-port network how hybrid parameter is expressed

- V
_{1}, I_{2} - Y
_{1}, I_{1} - I
_{1}, I_{2} - V
_{1}, V_{2}

17. When analysing two port network in cascade, which of the following is more convenient to use?

- z-parameters
- h-parameters
- T-parameters
- y-parameters

18. A two port network is reciprocal if

- Y
_{11}= Y_{22} - Y
_{12}= Y_{21} - Y
_{12}= -Y_{21} - Y
_{22}= Y_{21}

19. For a two port reciprocal network, the three transmission parameters are given by A = 3/5, B = 7/5, C = 4/5, what is the value of D?

- 1
- 3/5
- 53/15
- 1/2

20. Which of the following expression shows correct function for ‘Y’ parameter in a two port network?

- (V
_{1}, V_{2}) = f(I_{1}, I_{2}) - (I
_{1}, I_{2}) = f(V_{1}, V_{2}) - (V
_{1}, I_{1}) = f(V_{2}, -I_{2}) - (V
_{1}, I_{2}) = f(I_{1}, V_{2})

21. Two terminals constitute a “Port”, if they satisfy port condition. The port condition indicates

- current entering one terminal is equal to the current leaving the other terminal
- current entering one terminal and leaving the other terminal is different
- no current must enter and leave a port
- all the above

22. A network is said to be reciprocal if

- Z
_{12}= Z_{21} - Y
_{12}= Y_{21} - AD – BC = 1
- all of these

23. Two port networks are connected in cascade. The combination is to represent as a single two-port networks. The parameters of the network are obtained by multiplying the individual

- z-parameter matrix
- h-parameter matrix
- y-parameter matrix
- ABCD parameter matrix

24. Which of the following conditions holds good for a 2-port network to be reciprocal?

- Z
_{11}= Z_{22} - h
_{12}= h_{21} - Y
_{12}= Y_{21} - BC – AD = -1

25. In terms of ABCD parameters, a two port network is symmetrical if and only if

- A = B
- B = C
- C = D
- D = A

26. A passive 2-port network is in a steady-state. Compared to its input, the steady state output can never offer

- higher voltage
- lower impedance
- greater power
- better regulation