In-depth studies have shown that the dielectric material has a significant influence on the characteristics of the capacitor. The study succeeded in revealing the relationship between permittivity and capacitance. At the same time, the free space permeability and the permeability of the plastic sheet were accurately determined. The obtained data confirm the theoretical structure by proving the influence of the insulator on the capacitance. Despite the possibility of false sources, the results remained consistent and provide important information about the properties of the dielectric material inside the capacitor.