Analysis of Buoyancy Force in Static Fluid: A Study of Submerged Lead Sinkers in Different Fluid Properties

Abstract

Archimedes' Principle states that a fluid exerts an upward buoyant force opposing a submerged object's weight. However, the precise empirical correlation between varying fluid chemical compositions and the resulting magnitude of weight loss requires clear experimental mapping. This study investigates the direct influence of fluid density on buoyant force and apparent weight variations. Lead masses (30 g, 60 g, and 100 g) were fully immersed in three distinct media corn oil, tap water, and dishwashing liquid while tracking volumetric displacement and scale-measured net weight reduction. The results demonstrated that higher fluid densities consistently increase buoyant force; the densest medium (dishwashing liquid) generated the greatest force at 0.1710 N, causing a 17.43% weight reduction in the 100 g mass. These empirical findings closely align with theoretical calculations, validating the predictable nature of hydrostatic behaviours and offering practical insights for engineering and marine system designs.