Question):- A capacitor and a resistor are connected in series with an a.c. source. If the potential difference across C, R are 120V, 90V respectively and if the r.m.s. current of the circuit is 3A, calculate the- 1. Impedance 2. Power factor of the circuit. Share with your friends Share 0 Deepak Kumar answered this Dear Student , Potential difference across the resistor VR = 90 V, so 90 = IR.Potential difference across the Capacitor VC = 120 V, so 120 = I1ωC.Therefore V = VR2+VC2 =902+1202 =8100+14400 = 22500 =150. 1 But Z = V / I= 150 /3 = 50 ohm. 2. we know tanϕ = VCVR = 12090 =43.This implies that cosϕ =35.So power factor = cosϕ = 35Answers are correct. Regards 2 View Full Answer