 Young–Laplace equation

The Young–Laplace equation gives the pressure jump across an interface as $\Delta p=\gamma \kappa$, with the sign set by the chosen normal and curvature convention.

The Young–Laplace equation describes the pressure difference across the interface of a curved liquid surface due to surface tension. It is a fundamental equation in fluid mechanics that quantifies how curvature affects the pressure inside and outside a liquid droplet or bubble.