Zman said:Are you saying that knowing c from experiment, and u from something else, then the value of e is found?
Electrical permittivity is a measure of a material's ability to store electrical energy in an electric field. It is a physical constant that determines how much a material can be polarized in response to an applied electric field.
Electrical permittivity is typically measured using a device called a capacitor, which consists of two conductive plates separated by an insulating material. The permittivity of the material between the plates can then be calculated based on the capacitance of the capacitor.
The terms electrical permittivity and dielectric constant are often used interchangeably, but there is a subtle difference. Electrical permittivity is a physical constant that is the ratio of the electric flux density to the electric field strength in a vacuum, while dielectric constant is the same ratio but in a specific material.
Electrical permittivity plays a crucial role in determining the properties of materials, such as their ability to conduct electricity, their response to electric fields, and their dielectric strength. It also affects the speed of electromagnetic waves traveling through a material.
The value of electrical permittivity can be affected by various factors, including temperature, pressure, and the presence of impurities in the material. It can also vary depending on the frequency and strength of the applied electric field.