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Choose the appropriate answer (10 x 2) 1. The driving point impedance of a network can be calculated from (a) V(s)/I(s) (b) I(s)/V(s) (c) V(s)I(s) (d) None of these (The terms have their usual meaning) 2. A resistance of 10 Ω  in parallel with a reactance of (j10) Ω . shall have a phase angle (a) 45 0 (b) 30 0 (c) 60 0 (d) None of these 3. A function f(t) is an even function if for all values of (f) (a) f(t) = f(-t) (b) f(t) = -f(-t) (c) f(t) = f(t + T) (d) f(t) = -f(t + T/2) 4. Which of the following gives the correct number of basic loops? (a) Equal to the number of branches (b) Equal to the number of links (c) Equal to the number of elements (d) Equal to the number of nodes 5. When a pure LC parallel circuit is in resonance, the circuit condition can be represented by (a) A short circuit (b) Normal parallel circuit (c) An open circuit (d) None of these 6. Function Ks/[(s + 2) (s + 3)] has (a) 2 zeros and 1 pole (b) 2 zeros and 2 poles (c) 1 zero and 1 pole (d) 1 zero and 2 ...

Choose the correct answer (10 x 2) 1. A certain curr ent source has the values I s  = 4μA and R s  = 1.2 MΩ. The values for an equivalent voltage source are (a) 4.8 µV, 1.2 MΩ (b)  1 V, 1.2 MΩ (c) 4.8 V, 4.8 MΩ (d) 4.8 V, 1.2 MΩ 2. In a two-source circuit, one source acting alone produces 12 mA through a given branch. The other source acting alone produces 10 mA in the opposite direction through the same branch. The actual current through the branch is (a) 22 mA (b) 12 mA (c) 10 mA (d) 2 mA 3. An RL low-pass filter consists of a 5.6 mH coil and a 3.3 kΩ resistor. The output voltage is taken across the resistor. The circuit's critical frequency is (a) 93.8 kHz (b) 93.8 Hz (c) 861 Hz (d) 86.12 kHz 4. A 15Ω resistor, a 220 µH coil, and a 60 pF capacitor are in series across an ac source. What is the bandwidth of the circuit? (a) 138 MHz (b) 10,866 Hz (c) 1,907 Hz (d) 138 kHz 5. Consider the following statements associated with two-port networks. ( a) Z 1...

Answer the following (10 x 2) 1. The number of branches in a graph is 8. The number of sub-graphs in the network is (a) 256 (b) 254 (c) 128 (d) 126 2. The dual of a parallel R-C circuit is a (a) Parallel RC circuit (b) Series RC circuit (c) Series RL circuit (d) Parallel RL circuit 3. The bandwidth of a series resonant circuit with R=10 KΩ, L= 20 mH, C = 5 µF is (a) 80 kHz (b) 800 kHz (c) 100 Hz (d) 1 GHz 4. The value of h22 of the circuit shown in the figure. (a) 0.3 (b) 20 (c) 3.33 (d) 0.05 5. The maximum value of mutual inductance of two inductively coupled coils leaving equal self-inductance of 6 mH is (a) 6 mH (b) 36 mH (c) 12 mH (d) 3 mH 6. A system has transfer function G(s) = 1/(s + 12). Its settling time and rise time respectively are (a) 0.33, 0.183 (b) 0.183, 0.33 (c) 0.077, 0.33 (d) 0.33, 0.077 7. A unity feedback system has the following forward transfer function: The steady-state error when the input is 15tu(t) is (a) 0 (b) 0.4 (c) Infinity (d) 2.1875 8. For a u...

Answer any four in brief (4 x 5) Final value theorem with example In the solution of Networks, Transient, and Systems sometimes we may not be interested in finding out the entire function of time f(t) from its Laplace Transform F(s), which is available for the solution. It is very interesting to find that we can find the first value or last value of f(t) or its derivatives without having to find out the entire function f(t). If F(s) is given, we would like to know what is F(∞), Without knowing the function f(t), which is Inverse Laplace Transformation, at time t → ∞. This can be done by using the property of Laplace Transform known as the Final Value Theorem. The final value theorem and initial value theorem are together called the Limiting Theorems. If f(t) and f'(t) both are Laplace Transformable and sF(s) has no pole in jw axis and in the R.H.P. (Right half Plane) then, Z parameters in terms of ABCD parameters Properties of Hurwitz polynomial If above all the stability criteria ...

Answer the following in brief (5 x 4) Restrictions on pole and zero locations in the transfer function. The restrictions on pole and zero locations in the Conditions For Driving Point Function with common factors in P(s) and Q(s) cancelled are listed below. The coefficients in the polynomials P(s) and Q(s) of network function N(s) = P(s)/Q(s) must be real and positive. Complex poles or imaginary poles and zeros must occur in conjugate pairs. (a) The real parts of all poles and zeros must be zero, or negative. (b) If the real part is zero, then the pole and zero must be simple. The polynomials P(s) and Q(s) may not have any missing terms between the highest and the lowest degrees, unless all even or all odd terms are missing. The degree of P(s) and Q(s) may differ by zero, or one only. The lowest degree in P(s) and Q(s) may differ in degree by at the most one. Compare the block diagram representation and signal flow graph. Block diagrams consist of Blocks - these represent subsystems-t...