Physics Ontology

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kk
Fundamental Constants

Coulomb Law Constant

Electrostatic constant k = 1/(4πε₀); appears in Coulomb's law and radial electric fields.

SI unit

N m² C⁻² (N·m²/C²)

Dimension: [ ML3T−2I−2 ][\,M L^3 T^{-2} I^{-2}\,]

Other units

  • N m² C⁻² (N·m²/C²)

Defined value

Fixed constant from the A-level data sheets.

8.99 × 109 N·m²/C²

Edexcel / A-level value