Electrical Circuits II

Daffodil International University Department of Electrical and Electronic Engineering Faculty of Engineering Midterm Examination, Fall-2026 Course Code: 0713-121 Course Title: Electrical Circuits II Section: A, B, C, D, E, F Level-Term: L1-T2 Teacher's Initial: MSA, KNA, MW Full Marks: 25 Exam Date: 28 October, 2026 Time: 1.5 Hours Answer ANY TWO from Questions 1 – 3, and ANY THREE from Questions 4 – 7. Q1. In a series R-L-C circuit, R = 100 Ω, L = 67 mH and C = 33 μF. If the supply voltage is, v(t) = 120 sin(377t) V, compute - (a) Real and Reactive power of the circuit. (b) The expression of instantaneous power of the circuit. CO-1 C(3) Q2. The voltage source v(t) of Fig. 2(b) has the waveform shown in Fig. 2(a). [Figure: Waveform of v(t)] Fig. 2(a) [Figure: Circuit diagram with voltage source v(t), 18 Ω and 6 Ω resistors] Fig. 2(b) (a) Determine the RMS value of voltage v(t). CO-1 C(3) 3 (b) Calculate the average power absorbed by the 6 Ω resistor. 2 Q3. Calculate I, I1, I2 in the circuit of Fig. 3. Also determine the power factor, real and reactive power supplied by the source. Consider f = 50 Hz. CO-1 C(3) 5 [Figure: Circuit diagram showing AC source connected to parallel branches of inductor and capacitor with resistors] Fig. 3 Q4. Determine the value of vo, and io in the circuit of Fig. 4. CO-2 C(3) 5 [Figure: AC circuit with independent and dependent sources, resistor, capacitor, and inductor] Fig. 4 Q5. (a) For the following circuit, find Vo, if Io = 0. CO-2 C(3) 2 [Figure: AC bridge circuit] Fig. 5(a) (b) For the following circuit: 1+2 (i) Calculate V1 using voltage divider rule, and (ii) Calculate Io using current divider rule. [Figure: AC circuit with parallel and series branches] Fig. 5(b) Q6. Find the Thevenin equivalent of the circuit in Fig. 6 as seen from terminals a-b. CO-2 C(3) 5 [Figure: AC circuit with independent current source, dependent current source, resistors, and capacitor] Fig. 6 Q7. Determine io in the circuit of Fig. 7 using appropriate method of analysis. CO-2 C(3) 5 [Figure: Multi-source AC circuit with dependent and independent sources] Fig. 7