buoyancy
part of speech
noun (buoyancy — uncountable)
meaning for a pupil
1) (science) The upward push that water (or air) gives to an object, which makes things float or feel lighter. tree →
2) The ability of something to float: «Cork has great buoyancy.» tree →
3) Cheerfulness and the ability to recover quickly from bad times: «her buoyancy of spirit». tree →
4) (money) When prices or business stay high and strong. tree →
sense in the lessons
In science lessons buoyancy explains why boats float and stones sink: an object floats if the upthrust of the water is as big as its weight. Salty water gives more buoyancy, so floating in the sea is easier than in a pool. Swimmers use buoyancy aids (armbands, floats). Related: upthrust, float, sink, density.
examples
- Buoyancy keeps the boat afloat. tree →
- A life jacket gives you buoyancy in the water. tree →
- It is easier to float in the sea because salt water gives more buoyancy. tree →
- We tested the buoyancy of different fruits: the orange floated. tree →
- Submarines change their buoyancy to dive and rise. tree →
- Despite losing the match, the team's buoyancy returned quickly. tree →
- The buoyancy of the air made his heart light. tree →
note
Say «BOY-un-see» (UK) or «BOO-yun-see» (US). Spelling trap: «buoy» comes first (u before o). Adjective: buoyant. Myth: heavy things can float if their shape pushes away enough water — a steel ship floats.
Trees and pragmatics
Every meaning and example of «buoyancy» parsed by Mova, each sentence with its dependency tree and frames.