Meniscus Formation

concave vs convex · adhesion vs cohesion · Young equation

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Physics: Young's equation: γ_SV = γ_SL + γ_LV·cosθ, balancing solid-vapor, solid-liquid, and liquid-vapor surface energies. Contact angle θ < 90° indicates wetting (water on glass, θ ≈ 20°); θ > 90° indicates non-wetting (mercury on glass, θ ≈ 140°). The Kelvin equation relates vapor pressure to curvature: ln(P/P₀) = 2γV_m/(rRT), explaining why small droplets evaporate faster (high curvature → high vapor pressure). Capillary condensation in porous materials follows the same principle.