What is the Coulomb constant?
The Coulomb constant is k_e = 8.9875517873681764e9 N·m^2·C^-2 (derived from CODATA 2018). It equals 1/(4πε₀).
Open the interactive PhysRef tool →Key facts
| Value | 8.9875517873681764e9 N m^2 C^-2 |
|---|---|
| Symbol | k_e |
| Relation | k_e = 1/(4πε₀) |
| Approximation | ≈ 8.99e9 |
| Source | Derived from CODATA 2018 |
Frequently asked questions
What is the value of the Coulomb constant?
k_e = 8.9875517873681764e9 N·m^2/C^2, often rounded to 8.99e9 or 9e9.
What is Coulomb's law?
The electrostatic force is F = k_e·q1·q2/r^2, where k_e = 1/(4πε₀).
How is k_e related to ε₀?
k_e = 1/(4πε₀), so it is computed directly from the vacuum permittivity.
Related pages
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