A series – – circuit is connected to a sinusoidal ac source of frequency
PHYSICS · Multi-part · CBSE · Physics · Alternating Current · Alternating Current
Problem
A series R–L–C circuit is connected to a sinusoidal ac source of frequency 50Hz. The component values are R=50Ω, L=0.20H and C=80μF.
(i) Write the expressions for the inductive reactance and the capacitive reactance in terms of the supply frequency and explain their physical significance.
(ii) Calculate the numerical values of the two reactances for the given data and hence obtain (XL−XC).
(iii) Using the result of part (ii), state whether the circuit current leads or lags the supply voltage and estimate the phase angle between them.
(iv) If the frequency of the source is gradually increased while keeping the component values unchanged, qualitatively describe how XL, XC and the phase angle will vary.