Epsilon Naught (ε₀): Definition, Value, and Uses
Epsilon naught (ε₀), also known as the permittivity of free space or the vacuum permittivity, is a fundamental physical constant that describes the ability of a vacuum to permit electric field lines. It plays a crucial role in electrostatics, electromagnetism, and Maxwell’s equations, governing the interaction between electric charges in a vacuum. Mathematically, ε₀ is defined as the proportionality constant in Coulomb’s law, which expresses the force between two point charges in a vacuum: F = 1 4 π ε 0 ⋅ q 1 q 2 r 2 F = \frac{1}{4 \pi \varepsilon_0} \cdot \frac{q_1 q_2}{r^2} where: F F F is the electrostatic force, q 1 q_1 q 1 and q 2 q_2 q 2 are the magnitudes of the charges, r r r is the separation between the charges, and ε 0 \varepsilon_0 ε 0 is the permittivity of free space. Value of Epsilon Naught (ε₀) The permittivity of free space has a fixed value given by: ε 0 = 8.854187817 × 10 − 12 F/m ( Farads per meter ) \varepsilon_0 = 8.854187817 \ti...