Physics > Alternating Current > 3.0 Some important terms
Alternating Current
1.0 Introduction
2.0 Alternating current and alternating voltage
2.1 Instantaneous current and voltage
2.2 Mean or average current and voltage
2.3 Root mean square current and voltage
2.4 Form factor
3.0 Some important terms
4.0 Circuit element in AC circuit
4.1 Pure resistor circuit
4.2 Pure inductor circuit
4.3 Pure capacitor circuit
4.4 Series $L-R$ circuit
4.5 Series $C-R$ circuit
4.6 Series $L-C-R$ circuit
4.7 Resonance series $L-C-R$ circuit
4.8 Quality factor
4.9 Summary
5.0 Power in AC circuit
3.4 Phasor diagram
2.2 Mean or average current and voltage
2.3 Root mean square current and voltage
2.4 Form factor
4.2 Pure inductor circuit
4.3 Pure capacitor circuit
4.4 Series $L-R$ circuit
4.5 Series $C-R$ circuit
4.6 Series $L-C-R$ circuit
4.7 Resonance series $L-C-R$ circuit
4.8 Quality factor
4.9 Summary
In the study of A.C. circuits, we shall come across alternating voltages and currents which have the same frequency but differ in phase with each other. It is found that the study of AC circuits becomes simple if alternating currents and voltages are treated as rotating vectors or more correctly as phasors.
The phase angle between the two quantities is also represented in the vector diagram.
A diagram representing alternating voltage and current as vectors with the phase angle between them is known as phasor diagram.
In the study of AC circuits, we shall come across alternating voltage and currents which have the same frequency but differ in phase with each other.
Example: $$V = {V_0}\sin \omega t$$$$i = {i_0}\sin \left( {\omega t + \phi } \right)$$
where, $\phi $ is the phase angle between alternating voltage and current.
The instantaneous values of $V$ and $i$ may be regarded as projections of $V_0$ and $i_0$ respectively if $V_0$ and $i_0$ are treated as rotating vectors or more correctly as phasors.
If we are intrested only in phase relationship, the phasor diagram may also be represented as,
