In an RLC series circuit, the resistor, the inductor, and the capacitor are connected in a series combination across an AC voltage source, and have resistance and reactances. The current and the voltage of the AC source vary sinusoidally over time, where they are out of phase with each other by a phase angle Φ. The voltage is either mostly in phase with the current for a resistive circuit, or leads the current for an inductive circuit, or lags the current for a capacitive circuit. According to Kirchhoff's loop rule, the instantaneous voltages across the resistor, the inductor, and the capacitor add to give the instantaneous source voltage. The current phasor can be represented by a phasor diagram. Similarly, the three voltage phasors are vectorially added to arrive at the source voltage phasor. The phasor diagram leads to the amplitude and the phase angle of the source voltage phasor. When the phase angle is positive, the circuit is more inductive, whereas if it is negative, the circuit is more capacitive.