sähkökenttävakioon

Sähkökenttävakio, often translated as electric field constant or permittivity of free space, is a fundamental physical constant denoted by the symbol $\epsilon_0$. It quantifies the ability of a vacuum to permit electric fields. Its value is approximately $8.854 \times 10^{-12}$ farads per meter (F/m). This constant appears in many equations in electromagnetism, including Coulomb's law, which describes the force between electric charges, and Maxwell's equations, which govern the behavior of electric and magnetic fields.

The permittivity of free space relates the electric displacement field to the electric field in a vacuum. Specifically, it is the proportionality constant that links the electric field strength to the electric charge density. In essence, $\epsilon_0$ represents the fundamental property of the vacuum concerning how it responds to the presence of electric charges and fields. It is a crucial component in determining capacitance and other electrical properties of devices and materials. The value of $\epsilon_0$ is precisely defined based on the speed of light in a vacuum ($c$) and the magnetic constant ($\mu_0$) through the relationship $c^2 = 1/(\epsilon_0 \mu_0)$.