FIELD: physics.
SUBSTANCE: section of a long line is placed vertically in a container with a liquid, said line being filled with the liquid in accordance with its level in the container and having a horizontal end section which is filled, in steps, with the liquid and emptied when the liquid enters the container and is removed from the container, respectively; electromagnetic oscillations are excited in the section of the long line. The electromagnetic oscillations in said section are excited at two different resonance frequencies f1 and f2 which correspond to different energy distribution of the electromagnetic field along said section of long line with the horizontal end section; these resonance frequencies are measured depending on the level z of the liquid in the container and combined functional processing thereof is carried out in accordance with the relationship 
EFFECT: high measurement accuracy and simple measuring process.
2 dwg
