Calculate the buoyant force from Archimedes’ principle: the weight of the displaced fluid.
| Buoyant force (N) | – |
Use this calculator to find the upward buoyant force on an object in a still fluid. The force equals the weight of the fluid the object pushes aside.
The formula is F = ρ V g. V is the submerged volume, not the whole object unless it is fully under. If F is larger than the object’s weight, it floats in this still-fluid model. Fresh water is about 1000 kg/m³; seawater is a little higher.
Fluid density (kg/m³): Density of the surrounding fluid.
Displaced volume (m³): Volume of fluid pushed aside, in cubic metres.
g (m/s²): Gravitational field. Usually 9.81 m/s² on Earth.
Buoyant force (N): Upward force from the displaced fluid.
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