Equations · equation

Coulomb's Law

Electrostatics · 1785

Equation: F = k·q₁q₂ / r²
Field: Electrostatics
Named After: Charles-Augustin de Coulomb
Year: 1785

Symbols

F force between two charges · q₁, q₂ the charges · r their separation · k = 1/(4πε₀) the Coulomb constant · like charges repel, opposite attract

Significance

Charges push and pull with the same inverse-square shape as Newton's gravity — but a staggering 10³⁶ times stronger between two protons, and in both signs. Measured with a torsion balance so delicate Coulomb could feel forces of a billionth of a newton; it holds atoms, molecules, and you together.

Minerals

Theories

Rutherford Model of the Atom Classical Electromagnetism

Related

Law of Universal Gravitation Fine-Structure Constant Debye Length Gauss's Law Electric Field Rutherford Scattering

Constants

Euler's number Pi Vacuum electric permittivity Elementary charge

Requires

Vector Magnitude Sphere: Surface and Volume

Referenced by

constant

Elementary charge Euler's number Pi Vacuum electric permittivity

equation

Debye Length Electric Field Fine-Structure Constant Gauss's Law Law of Universal Gravitation Rutherford Scattering Sphere: Surface and Volume Vector Magnitude

theory

Classical Electromagnetism Rutherford Model of the Atom

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From the Equations database in Notion, last edited 2026-08-18. This page is the row, rendered by the build; nothing on it is written by hand.