center of mass
Let an agent explain the centre of mass and its relatives, relay definitions, calculation and applications from mechanics references, describe centroids, barycentres and centres of buoyancy, and distinguish centre of mass from centre of gravity in non-uniform fields, from the centroid of a shape and from the centre of pressure.
Research draft, second pass
A second pass drafted this model: the structure a model of this thing needs, and what is known about it in the world. The line under this one says how the second half was obtained - researched against sources, or recalled without web access, in which case nothing here was read anywhere and every claim is a lead to verify. Unreviewed either way.
written by Claude from model knowledge without web access - no source was read, every claim is a lead to verify
Researched by: Claude
Purpose and description
Let an agent explain the centre of mass and its relatives, relay definitions, calculation and applications from mechanics references, describe centroids, barycentres and centres of buoyancy, and distinguish centre of mass from centre of gravity in non-uniform fields, from the centroid of a shape and from the centre of pressure.
The unique point of a body or system where its mass is concentrated for the purposes of mechanics, so that the body balances there and external forces act on it as if applied at that point, coinciding with the centre of gravity in a uniform gravitational field and with the geometric centroid for uniform density, with the triangle centroid a classic example, the barycentre of orbiting bodies an astronomical case, and the centre of buoyancy the analogous point for displaced fluid.
What it is for: Analysing balance, motion and stability.
It can be explain the concept; relay calculation and applications; describe related points; distinguish related concepts.
Distinguishing features
Mass-weighted point
Newtonian mechanics
Several related points
Stability analysis
What it looks like
Not a visible object; a point in a body or system.
Physical character
definition: mass-weighted mean of positions note
Earth-Moon barycentre: about 4670 km from Earth s centre note - inside the Earth
triangle centroid: intersection of medians note
How it is recognised
Mass-weighted average position
Centre of gravity, centroid, triangle centroid, barycentre, centre of buoyancy
Centre of gravity differs in non-uniform fields; the centroid is geometric; centre of pressure concerns fluid forces
Related models
is a kind of - in registry terms
is a kind of - in registry terms
coincides with - for uniform density
is contrasted with - for fluid forces
In practice
Families and kinds
centre of mass of rigid bodies and systems
centre of gravity in uniform and non-uniform fields
centroids of shapes including the triangle centroid
barycentres of orbiting systems
centre of buoyancy in fluids
Standards and regulation
No regulation; engineering standards for stability and loading
Failure modes and hazards
Confusing centre of mass and centre of gravity
Instability from misplaced loads
Registry aliases mixing related but distinct points
Also called
Where this came from
wikidata · CC0 1.0
Drafted structure
Bundle to layer to finding to question, as the second pass will find it: 4 bundles · 8 layers · 8 findings · 16 questions.
Understand What the centre of mass is.
Science.
Definition
Definition.
Definition
Definition.
- What is the centre of mass, and how does it differ from centre of gravity, centroid and centre of pressure? definition
- Is the question about mechanics, geometry, astronomy or fluids? boundary
Related
Related points.
Related
Related.
- What are the triangle centroid, the barycentre and the centre of buoyancy? definition
- Which entry fits the specific point? action
Compute Calculation.
Practice.
Methods
Methods.
Methods
Methods.
- How is the centre of mass calculated for particles, shapes and composite bodies? action
- Which references are standard? provenance
Experiment
Finding it experimentally.
Experiment
Experiment.
- How is the centre of mass found by suspension and balancing? measurement
- Which sources are cited? provenance
Apply Applications.
Application.
Engineering
Engineering.
Engineering
Engineering.
- How is centre of mass used in vehicle, aircraft and ship stability and in structures? provenance
- Which entry fits ship stability? action
Astronomy
Astronomy and sport.
Astronomy
Astronomy.
- How do barycentres govern orbits, and how do athletes use centre of mass in movement? provenance
- Which entry fits barycenter? action
Context Theory and history.
Context.
Theory
Theory.
Theory
Theory.
- Why does the centre of mass move as if all external forces act on it, and what changes in relativity? provenance
- Which entry fits Newton s laws of motion? action
History
History.
History
History.
- How did Archimedes and later scientists develop the concept? provenance
- Which entry fits the history of mechanics? action
What the second pass must settle
- Should centroid, barycentre and centre of buoyancy be separate primary entries?
- How should mechanics references be linked?
- The registry entry has merged aliases naming distinct points; should they be split off?