  The present paper is devoted to consideration and discussion of a number of
contradictions that take place in fundamental electrodynamics researches. A
concept of the scalar-vector potential is introduced that allows us to avoid a
number of challenges taking place in treatment of forces of elecrtromagnetic
interaction. It is introduced the delayed scalar-vector potential allowing one
to solve radiation problems at an elementary level. It is shown that in a
nonmagnetized plasma, beside the earlier known longitudinal Langmuir resonance,
there may exist a resonance transversal relative to the wave propagation
direction. It is also shown that the dielectric and magnetic permittivities are
independent on the frequency. It is introduced a concept of the kinetic
capacitance.
