Circuit Theory & Network Analysis — DU B. Sc. (Hons) Electronics Previous Year Question Papers

(c) Define Resonance in Series RLC Circuit. Obtain the expressions for resonant frequency coo, the two half power frequencies col and co2, bandwidth 8 and the quality factor Q for the Series RLC 1. (a) Differentiate between an Ideal and Pract`ical voltage source with the help of symbolic representation and I-V characteristics. (3) (b) Find the rms .value of the current wave form shown in figure below. (3) (c) Calcrilate the c.urrent io through 4Q resistor for the circuit given below. (3) 7. (a) Design a Low-Pass RC Filter having cut-off frequency fc = 2.4 KHz. Draw the frequency response of the designed circuit. (6) (b) A Series circuit comprises a 10 a resistance, a 5 LtF capacitor, and a variable inductance,L. The supply voltage is 20 ZOO volts at a frequency of 318.3 Hz. The inductance is adjusted until the p.d. across the loo resistance is a maximum. Determine for this condition (i) the value of inductance L, (ii) the p.d. across each component, and (iii) the Q-factor. (b) For I = 33 Z -13° Amp, find the Thevenin equivalent of the followin,g circuit. (c) Find the value of load impedence in the following circuit to extract maximum power from th.e source. (4) (d) Explain the Principle of Duality in electrical networks. Give one example of a dua-1 pair. (3) (e) Different.iate between the ideal and practical response of High pass RC Filter. (3) (D Write down the formulae for converting a delta netwiork (consisting of Z„ Z2 and Z3) into a Star network (consisting of zA, ZB and zc). (3) 2. (a) Apply the mesh current method to the network shown below and write the matrix equations by inspection. Obtain current 1]. Also obtain Contribution of each source to I]. (6) (b) Solve for the mesh currents in the network shown below by using node voltage method. (c) (i) Convert the following Star networ.k to its equivalent Delta network. (6) lo n loft agivwFn_a (b) State and prove Maximum Power Transfer theorem. (8) (c) Calculate the voltage v o across 8 ohm resistor by transforming the current source to voltage source in the following circuit. 6. (a) Find Millman's equivalent for the left of the terminals x-y after converting current source to voltage source. (6) 5. (a) Find theNorton equivalent of the following circuit i across terminals a-b. (6) (ii) Convert the following Delta Network to its equvalent Star network. 3. (a)Wh.at are the various types 9f controlled sources. Explain briefly using symbolic represtation. (b) In the circuit shown below, what is the power absorbed by each element. (7) (c) Determine the value of input impedance of the following circuit at co = 50 rad/s. (b) Find the value of current (12) flowing through capacitor in the following circuit using Mesh analysis. 4. (a) In the following circuit, find the (i) average power supplied by the source, (ii) average power absorbed by the resistor and (iii) average power absorbed by the capacitor. (6) (c) Find the rms value of the current wave form shown in figure below (6)