Equations · equation

Wave Equation

Acoustics · 1746

Equation
∂²u/∂t² = c²·∇²u
Field
Acoustics
Named After
Jean le Rond d'Alembert
Year
1746

Symbols

u the disturbance (string displacement, air pressure, field strength) · t time · c wave speed · ∇² Laplacian (spatial curvature of the disturbance)

Significance

One equation for everything that waves: a plucked string, sound in air, ripples on water — and, a century later, Maxwell found light obeying the very same form. Derived by d'Alembert for the vibrating string, it is the mathematical definition of what a wave is.

Theories

Related

Requires

Required By

Referenced by

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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.