Ring waves on the surface of a liquid in a Coulomb field

Regularities of realization of instability of ring waves on the surface of conductive liquid in the Coulomb field are investigated. The relation for connection of frequency of ring capillary and gravitational waves on a surface of liquid in non-uniform electrostatic field of a dot charge with physical parameters of a task and with an analog of wave number is brought. By analogy with the field parameter of Tonks–Frenkel the field parameter characterizing stability of a surface of conductive liquid in the non-uniform Coulomb field is determined. It is found that critical conditions of realization of instability of ring waves on the surface of conductive liquid in the Coulomb field are more soften than critical conditions of realization of instability of Tonks–Frenkel.