# Circuit containing Capacitor and resistance in series|Alternating Current

## Circuit containing capacitance and resistance in series

- Figure below shows a circuit containing capacitor and resistor connected in series through a sinusoidal voltage source of voltage

V=V_{0}sin(ωt+φ)

- In this case instantaneous P.D across R is

V_{R}=IR

and across the capacitor C is

V_{C}=I/ωC

- In this case V
_{R} is in phase with current i and V_{C} lags behind i by a phase angle 90_{0}

- Figure 11(b) shows the phasors diagram where vector OA represent the resultant of V
_{R} and V_{C} which is the applied Voltage thus

is called the impedance of the circuit

- Again from the phasors diagram applied voltage lags behind the current by a phase angle φ given by

tanφ= V_{C}/ V_{R}=1/ωCR ---(18)