ABSTRACT
This chapter shows how to construct a phasor diagram for a series a.c. circuit. By constructing a phasor diagram, solving an 'electrical' problem becomes a simple matter of applying either basic geometry (Pythagoras's Theorem) or basic trigonometry (sine, cosine or tangent ratios) to simple right-angled triangles. For example, by applying Pythagoras's Theorem to each of the voltage phasor diagrams, which are really just simple right-angled triangles, the relationships are revealed. We can convert each of the voltage phasor diagrams into a corresponding impedance diagram, by simply dividing throughout by the reference phasor, I. Once we have learnt to construct a phasor diagram for a parallel a.c. circuit, solving an 'electrical' problem becomes a simple matter of applying either basic geometry (Pythagoras's Theorem) or basic trigonometry (sine, cosine or tangent ratios), where the phasor diagrams are simple, right-angled triangles.
