R-C Circuit

Topic Content:

Series R-C Circuit:

An a.c. circuit containing a capacitor and a resistor connected in series is called an R-C Series Circuit .

A typical R-C circuit is shown in the diagram below:

Series R-C Circuit Phasor (Vector) Diagram:

• The reference vector is labelled I  and represents the current in the circuit, which is common to all circuit elements. This is similar to the R-L circuit.

• For a capacitor, the current I leads the voltage V_C  by 90 degrees; therefore, the capacitor voltage V_C  lags the current I by 90 degrees and is drawn lagging the current vector by 90 degrees, as represented by the red line in the phasor diagram.

• In a resistor, the current through the resistor remains in phase with the voltage drop