Upthrust equals the weight of fluid displaced.
Archimedes: buoyant force equals weight of displaced fluid F_B=ρ_f g V_disp. Floats if average density is below the fluid's. Stability requires the metacentre above the centre of gravity. Hydrometers, ships and balloons rely on it.
A 50 000 tonne ship displaces 50 000 m³ of seawater (approx.).
Buoyancy explains why objects float or sink and is needed for ship stability, submarine control and density measurement.
Upthrust equals the weight of fluid displaced.
Buoyancy explains why objects float or sink and is needed for ship stability, submarine control and density measurement.
The buoyant force equals the weight of fluid displaced, which acts upward through the centre of buoyancy.
The average density of the hull and air inside is lower than water, so the displaced water weighs more than the ship.
Typical applications include checking whether a boat hull floats at its design draught, calculating the buoyant force on a sensor pod submerged in water and determining whether a floating platform is stable under wave loads.
Study "Manometers and pressure measurement" first (topic 48 of 105 in Thermodynamics & Fluids). It covers the groundwork this topic builds on.
Centre of buoyancy. Metacentric height GM. Ballast.
A 50 000 tonne ship displaces 50 000 m³ of seawater (approx.).
The next topic is "Forces on submerged surfaces", which builds directly on this one.
It is classed as Intermediate in Thermodynamics & Fluids (topic 49 of 105). It is an intermediate topic. Work through the beginner topics in Thermodynamics & Fluids first.
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