2025 Exam Questions
Q. In a series LCR circuit, if resistance, inductive reactance and capacitive reactance are 3 \Omega, 8 \Omega and 4 \Omega respectively, calculate phase difference between voltage and current.
Q. Obtain an expression for average power dissipated in a series LCR circuit.
2024 Exam Questions
Q. Derive an expression for the impedance of an LCR circuit connected to an AC power supply. Draw phasor diagram.
Q. An alternating voltage is given by e = 8 sin 628.4 t. Find
(i) peak value of e.m.f.
(ii) frequency of e.m.f.
(iii) instataneous value of e.m.f. at time t = 10 ms.
2023 Exam Questions
Q. What is the average value of alternating current over a complete cycle?
Q. An alternating voltage given by e = 140 sin (314.2 t) is connected across a pure resistor of 50 Ω.
Calculate:
i) the frequency of the source
ii) the r.m.s. current through the resistor
Q. A 100 Ω resistor is connected to a 220 V, 50 Hz supply.
Calculate:
i) r.m.s. value of current and
ii) net power consumed over the full cycle
2022 Exam Questions
Q. The average value of alternating current over a full cycle is always _____.
(I0 = Peak value of current)
(A) zero
(B) \frac{I_0}2
(C) \frac{I_0}{\sqrt2}
(D) 2 I0
Q. Define:
i) Inductive reactance
ii) Capacitive reactance
iii) Impedance
Q. A 0.1 H inductor, a 25 x 10-6 F capacitor and a 15 Ω resistor are connected in series to a 120 V, 50 Hz AC source. Calculate the resonant frequency.
Q. A 1000 mH inductor, 36 μF capacitor and 12 Ω resistor are connected in series to 120 V, 50 Hz AC source. Calculate:
i) impedance of the circuit at resonance
ii) current at resonance
iii) resonant frequency
