Physics: Permittivity of free space

Wikimedia Commons, CC BY-SA

Condensed Matter Electromagnetism Optics

Permittivity of free space ε₀ = 8.854×10⁻¹² F/m In electromagnetism, the absolute permittivity, often simply called permittivity and denoted by the Greek letter ε (epsilon), is a measure of the electric polarizability of a dielectric material.

Commentary

Permittivity of free space Symbol: ε₀ = 8.854×10⁻¹² F/m In electromagnetism, the absolute permittivity, often simply called permittivity and denoted by the Greek letter ε (epsilon), is a measure of the electric polarizability of a dielectric material. Why ε₀ matters This constant appears everywhere in physics equations. It defines a fundamental limit or relationship in nature that holds true everywhere in the universe. D = ε E . {\displaystyle \mathbf {D} =\varepsilon \ \mathbf {E} ~.} Understanding ε₀ ε₀ = 8.854×10⁻¹² F/m In electromagnetism, the absolute permittivity, often simply called permittivity and denoted by the Greek letter ε (epsilon), is a measure of the electric polarizability of a dielectric material. A material with high permittivity polarizes more in response to an applied electric field than a material with low permittivity, thereby storing more energy in the material. In electrostatics, the permittivity plays an important role in determining the capacitance of a capacitor. In the simplest case, the electric displacement field D resulting from an applied electric field E is D = ε E . {\displaystyle \mathbf {D} =\varepsilon \ \mathbf {E} ~.} More generally, the permittivity is a thermodynamic function of state. It can depend on the frequency, magnitude, and direction of the applied field. The SI unit for permittivity is farad per meter (F/m). The permittivity is often represented by the relative permittivity εr which is the ratio of the absolute permittivity ε and the vacuum permittivity ε0

Sources: Wikipedia