buoyancy: Quick Facts

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Facts

Also Known As	flotation

Photos and Videos

Illustration showing Archimedes' principle: a 5 kg weight is weighed in air, then submerged in water, where it appears to weigh 2 kg; a separate container shows 2 kg of displaced water, demonstrating buoyant force.

Diagram showing how a ship stays upright, with arrows indicating the downward force of gravity at the center of gravity (G) and the upward force of buoyancy at the center of buoyancy (B), both in level and tilted positions.

Diagram showing a teleost fish, specifically a perch, with a side view and a labeled cross section. The cross section identifies internal structures including muscle, vertebra, neural spine, nerve cord, dorsal aorta, dorsal and ventral ribs, swim bladder, coelom, and stomach. The side view shows the location of the swim bladder and stomach inside the fish.

A bright yellow submersible explores an underwater cave, surrounded by rocks, aquatic plants, and schools of fish illuminated by blue light from above.

Hot-air balloon

Diagram showing three orientations of a uniform square prism floating in liquid of twice its density, with the stable position labeled C. Each prism is half submerged, and points B and C are marked to indicate centers of buoyancy and gravity.

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Topics

centre of buoyancy metacentre Why does ice float on water?Archimedes’ principle fluid Magnus effect Pascal’s principle boundary layer thixotropy cavitation

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