Passive Electrical Circuits

Passive circuit elements are components that do not generate current or potential. A passive electrical circuit is composed only of passive elements. Only an element with two contacts is considered here, which is analyzed by considering the current flowing through and the potential difference between the contacts, shown as open circles in Figure 4.1. 

In electrolysis, both terminals of the electrochemical cell are connected to an external source which supplies the energy needed to produce a non-spontaneous reaction in the electrochemical system. Therefore the latter behaves as an electric load, and the direction of the current is dictated by the external power supply. It is worth recalling that in a passive electric circuit the current flows in the direction towards the decreasing potentials from the positive pole of the power supply towards the negative pole in the external circuit. In a simple electric representation, the circuit is as shown in figure 1.8 . ... 

Causal system A system whose output does not depend on future input the output at time t may depend only on the input signal /(t) X < t. For example, the voltage measured across a particular element in a passive electric circuit does not depend upon future inputs applied to the circuit and hence is a causal system. 

If a system satisfies the conditions of linearity, stability, and causality, it will a priori satisfy the KK transforms, provided that the frequency range is sufficiently broad for the integrals to be evaluated. Accordingly, passive electric circuits provide an absolute measure against which any numerical algorithm for evaluating the integrals can be assessed. ... 

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