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How did Archimedesā principle explain why objects float or sink?
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Archimedes
Archimedes, oil on canvas by Giuseppe Nogari, 18th century; in the Pushkin Fine Arts Museum, Moscow. Archimedes was an ancient Greek mathematician and inventor.
Archimedesā principle explains that any object submerged in a fluid experiences an upward buoyant force equal to the weight of the fluid it displaces. Whether an object floats or sinks depends on the relationship between its own weight and this buoyant force.12
- Floating: An object floats if the buoyant forceāthe weight of the displaced fluidāis equal to or greater than the object's weight. For instance, a ship sinks only until the weight of the water it displaces matches its own weight, at which point it remains stable.12
- Rising: If an object weighs less than the fluid it displaces, the buoyant force exceeds the object's weight, causing it to rise to the surface.1
- Sinking: An object sinks if it is heavier than the amount of fluid it displaces. While it will sink, it still experiences an apparent weight loss equivalent to the weight of the displaced fluid.1
This phenomenon occurs because fluid pressure increases with depth, creating a net upward force that opposes gravity.1