AC through resistor, capacitor and inductor (tabular form)



Type of circuit Value of current Total impedance Remarks
R circuit I=E/R Z=R Both current and emf are in phase
L circuit I=E/XL Z=XL=Lw Current lags emf by π/2
C circuit I=E/XC Z=XC=1/Cw Current leads emf by π/2
LR circuit I=E/Z Z=√(R2+XL2) where XL=Lw In R: Both current and emf are in phaseIn L: Current lags emf by π/2

So θ=tan-1(Lw/R)

RC circuit I=E/Z Z=√(R2+XC2) where Xc=1/Cw In R: Both current and emf are in phaseIn C: Current leads emf by π/2

So θ=tan-1(-1/CwR)

LCR circuit I=E/Z Z=√{R2+(XL-XC)2 }where Xc=1/Cw, XL=Lw In R: Both current and emf are in phaseIn C: Current leads emf by π/2

In L: Current lags emf by π/2

So θ=tan-1{(Lw-1/Cw)/R}