Capacitive transducers operate based on the principle of capacitance, which is the ability of a system to store an electric charge. The capacitance (C) of a parallel-plate capacitor is given by the formula: C = ε₀ * ε_r * A / d where ε₀ is the permittivity of free space, ε_r is the relative permittivity of the dielectric material, A is the area of the plates, and d is the distance between the plates. Any change in the distance (d), area (A), or dielectric material (ε_r) will result in a change in capacitance, which can be measured and correlated to the physical quantity being sensed.
