Archimedes' principle — a submerged body experiences a buoyant force equal to the weight of the displaced liquid.
Symbols
Fw
buoyant force
[N]
ρ
density of the liquid
[kg/m³]
g
gravitational acceleration
[m/s²]
V
volume of the submerged part
[m³]
Where it comes from
A submerged body experiences a buoyant force equal to the weight of the displaced liquid (Archimedes' principle). When the buoyancy exceeds the weight, the body floats; when it is smaller, it sinks.
When to use it
Floating, determining density, balloons (buoyancy in a gas).
Example
A body of volume 0.002 m³ is submerged in water (ρ=1000, g=10). Calculate the buoyant force.