B.E Third Semester Examination, Dec-2010
A Model Question Paper
(a) Write a mesh equation for the circuit shown in figure-1 and determine mesh currents using mesh analysis.
(b) Obtain expression for a set of equivalent.
i) Y connected impedance to replace a set of delta connected impedance.
ii) Delta connected admittance to replace a set of Y connected admittance.
(c) Distinguish between the Independent and dependent sources with one example. (6+10+4=20 Marks)
2 (a) Explain briefly tree, co-trees, and loops in a graph of network with suitable example.
(b) Under what condition do you consider topology for network analysis? For the graph shown in figure-2, for a co-tree (4, 5, 2, 8), write the tie set and cut-set matrices.
(c) Explain incidence of a graph with a suitable example.
3 (a) State and explain i) reciprocity theorem ii) Millman’s theorem
(b) State and explain superposition theorem.
(c) Determine the current through 2 Ω resistor of the network shown in figure-3 using superposition theorem. (10+5+5=20 Marks)
4 (a) State and explain Norton’s theorem.
(b) Sate and explain maximum power transfer theorem.
(c) In the network shown in figure-4 determine the impedance ZL for which power transfer is maximum. Calculate the maximum power transfer to the load.
4 (a) Show that series resonant frequency of series resonance circuit is equal to the geometric mean of two half power frequencies.
(b) What is the difference between selectivity and bandwidth? Explain.
(c) A coil of inductance 31.8mH and resistance 10Ω is connected in parallel with a capacitance across 220V, 50 Hz supply. Determine value of C if non inductive current flows in circuit. (6+4+10=20 Marks)
6 (a) In the circuit shown in figure-5, determine the complete solution for the current when the switch S is closed at t = 0. Applied voltage is v(t) = 400 cos(500+pi/4) resistance R= 15 Ω, inductance L = 0.2 H and capacitor C= 3µF.
(b) Explain A.C excitation of series R-C circuit. (10+10=20 Marks)
7 (a) State and prove i) initial value theorem and (ii) final value theorem as applied to L transform. What are the limitations of each theorem.
(b) Find the Laplace transform of the periodic signal shown in the fig-6
7 (a) Define Y and Z parameters. Derive relationship such that Y-parameters expressed in terms of Z-parameters and Z-parameters in terms of Y-parametrs.
(b) Find the transmission parameters for the network shown in figure-7.
(10+10 =20 Marks)
NOTE: If you are confused about which unit should I select for exam, then I’m going to tell you in next post.