Conductance Under High A.C. Frequencies
Debye-Falkenhagen examined the conductance behaviour of strong electrolytic solutions by applying alternating current (AC) of different frequencies. They observed that the conductivity of an electrolytic solution increases when voltage of a very high frequency is applied. This is known as the Debye–Falkenhagen effect.
They predicted that if the frequency of alternating current is high so that the time of oscillation is less than the relaxation time of the ionic atmosphere, the asymmetry effect will be almost absent. That is, the ionic atmosphere around the central ion will remain symmetric. In such a situation, the retarding effect due to asymmetry will be entirely absent and the conductance may be higher. The conductance of the solution, therefore, should vary with the frequency of the alternating current used.
Higher the frequency, higher the conductance—this effect, also termed dispersion conductance, has been experimentally verified.
The conductance is independent of the frequency of alternating current up to 10 cps (cycles per second). But with further increase of frequency, the conductance increases towards a certain limiting value. This shows the complete absence of the asymmetry effect under high-frequency alternating current.
Related Topic: Wien Effect ➤