The equivalent impedances of inductor and capacitor in transient response were deduced from the exponential transient solution and the volt ampere relation of these elements.

RL circuit is taken into consideration, in which the transient current signal includes a period component varying in sinusoidal waveform and a non-period component varying in exponential waveform.

Mobile ion transient equations are solved with MATLAB and the time-dependent distributions in the forms of negative-index exponential function are obtained.