buoyancy

References & Edit History Quick Facts & Related Topics

Images & 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.

Why do objects float or sink in water?

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.

How Did the Montgolfier Brothers' Hot-Air Balloon Contribute to Aviation?

Know how some spiders walk on the surface of the water

How phytoplankton function and survive in the ocean

buoyancy: References & Edit History

More Articles On This Topic

Article Contributors

Primary Contributors

Ken Stewart
Ken Stewart is a former educator with an honours degree in chemistry, physics, and mathematics.

Other Encyclopedia Britannica Contributors

Tara Ramanathan

Article History

Type	Description	Contributor	Date
	Article updated and revised.	Tara Ramanathan	Oct 15, 2025
	Added new article.	Tara Ramanathan Ken Stewart	Feb 10, 2023