The Use of j-Notation in Circuit Analysis

In programmes 2 and 3 we established the main body of theory needed to analyse circuits containing direct voltage and current generators and resistors. We saw how a very wide range of circuit problems could be reduced, by the use of Thevenin and Norton’s theorems, to the analysis of two simple forms: the potential divider and the current splitter. In programme 4 we investigated the nature of time-varying waveforms (voltages and currents which are not direct but whose values change with time) and learnt that sinusoidally varying signals in particular are very widely used in circuit design. In programme 4 we saw how the mathematical properties of such waveforms could be represented by a vector-like ‘phasor notation’ and went on to see how this notation could be used in circuit analysis.