In a laboratory experiment an inductor of 80 mH is connected in series with a…
PHYSICS · Multi-part · CBSE · Physics · Alternating Current · Alternating Current
Problem
In a laboratory experiment an inductor of 80 mH is connected in series with a capacitor of 5 µF to an AC source; the resistance of the coil is negligible.
(i) Determine the magnitude and sign (inductive or capacitive) of the reactive quantity XL−XC at a frequency of 400 Hz.
(ii) Repeat the calculation for a frequency of 900 Hz.
(iii) Calculate the magnitude of the impedance Z at each of the two frequencies.
(iv) From your answers, state whether the circuit current leads or lags the source voltage at each frequency and identify the frequency at which the circuit would become purely resistive.