Air permittivity of dielectric constants

The dielectric constant of air is how many common substances have a dielectric constant table

The relative dielectric constant of air is 1, dry air is a good dielectric and is used in variable capacitors as well as certain types of transmission lines.

The smallest, generally approximate, is the dielectric constant of the vacuum, with an approximation of 1, and others are greater than one.

What is the dielectric constant and what is the dielectric constant unit?

Dielectric constant (also known as permittivity), expressed as ε, ε = εr * ε0, ε0 is the vacuum absolute dielectric constant, ε0 = 8.85 * 10 ^ (-12) F / m. It should be emphasized that the dielectric constant value of a material is closely related to the frequency of the test.

When a capacitor plate is filled with a substance having a dielectric constant of ε, the capacitance becomes εr times larger. The dielectric has properties that make the space larger or smaller than the actual size. For example, when a dielectric material is placed between two charges, it reduces the force acting between them as if they were moved away.

As electromagnetic waves pass through the dielectric, the speed of the waves is reduced and there are shorter wavelengths.

The polarity of the polymer material can be discriminated based on the dielectric constant of the substance. Generally, a substance having a relative dielectric constant of more than 3.6 is a polar substance; a substance having a relative dielectric constant of 2.8 to 3.6 is a weakly polar substance; and a relative dielectric constant of less than 2.8 is a nonpolar substance.

The dielectric constant is in F/m.

Dielectric constant values of common substances:

The dielectric constant of air is how many common substances have a dielectric constant table

Relative dielectric constant values of common substances and electromagnetic wave propagation speed

Among them, the dielectric constant of air is close to 1, the dielectric constant of most anhydrous substances (such as dry soil and rock), the real part is generally between 1.7-6, and the dielectric constant of water is generally 81. The imaginary part is small and generally negligible.