What is permittivity, in electricity?
Permittivity is a property of a material that measures the way charges in that material separate in an electrostatic field – the material is said to “polarise” to a greater or lesser extent. The most easily understood example is that if you use a material as the insulator (dielectric) in a capacitor, then if all dimensions are kept the same, the capacitance of that capacitor is proportional to the permittivity of the material.
