Processes following changes of phase angle between current and voltage in electric circuits

Investigations of the changes of current frequency in R, L electric circuits supplied with 50 Hz sinusoidal voltage during changes of the phase angle between current and voltage are presented. Changes of reactance of the electric circuit are demonstrated as consequences of change of current frequency during the transient process, which is a possible new explanation of the occurrence of the aperiodical component of the current. For fast transient processes of phase angle change, current frequency is different from the voltage frequency.