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Published

radius

vr.tr.radius · thing-q173817

Let an agent explain and compute radii in geometry and applications, distinguish specialised radii, and separate the anatomical sense.

Thing Registry Cross-cutting context XCT.QLT
Bundle → Layer → Finding → QuestionsClassifiersWhat it isWhy it existsDistinguishing featuresWhat robots and AI may and may not doMoral aspectsOwnersLinks to other meta-modelsIdentity and identifiersDirect propertiesRecognitionCapabilities and actionsHazards and failure modesStandards and interfacesContext of useSources

Bundle → Layer → Finding → Questions Filled

4 bundles · 8 layers · 8 findings · 16 questions

Compute Finding the radius.

Circle

Circles and spheres.

Circle

Circles.

  1. What is the radius given the diameter, circumference, area or volume? measurement
  2. How does the radius enter these formulas? definition

Curvature

Radius of curvature.

Curvature

Curvature.

  1. What is the radius of curvature of this curve or surface at this point? measurement
  2. How does it relate to curvature? definition
Apply Engineering radii.

Bend

Minimum bend radius.

Bend

Bend radius.

  1. What minimum bend radius applies to this cable, pipe or sheet, according to the standard? provenance
  2. What happens if it is exceeded? boundary

Parts

Radii on parts.

Parts

Parts.

  1. How are radii specified on drawings for shafts, fillets and pipes? provenance
  2. Which tolerances apply? measurement
Physics Physical radii.

Schwarzschild

Schwarzschild radius.

Schwarzschild

Schwarzschild radius.

  1. What is the Schwarzschild radius, and what is it for this mass? measurement
  2. What does it mean physically? definition

Atomic

Atomic and ionic radii.

Atomic

Atomic radii.

  1. How are atomic and ionic radii defined and measured? definition
  2. How do they vary across the periodic table? provenance
Senses Disambiguation.

Bone

The radius bone.

Bone

Anatomical sense.

  1. Is the forearm bone meant? boundary
  2. Which entry fits? action

Teach

Teaching.

Teach

Teaching.

  1. How can radius and diameter be taught without confusion? action
  2. Which misconceptions arise? provenance

Classifiers Filled

Family
Thing Registry
Category
Cross-cutting context
Entry kind
thing
Plane
XCT
Domain
XCT.QLT
Other names and narrower kinds
radius of curvature, Schwarzschild radius, minimum bend radius, pipe radius, shaft radius, inner annulus radius, outer annulus radius, radial coordinate, gyroradius, effective radius, mean radius, Potato radius

What it is Filled

A line segment from the centre of a circle or sphere to its boundary, and the length of that segment, half the diameter, extended to related measures such as the radius of curvature of a curve, the radius of a pipe or shaft, and specialised radii such as the Schwarzschild radius and minimum bend radius; the radius is fundamental to geometry, engineering and physics, and is also the name of a forearm bone.

Why it exists Filled

Let an agent explain and compute radii in geometry and applications, distinguish specialised radii, and separate the anatomical sense.

Distinguishing features Filled

  • Centre-to-boundary length
  • Defines circles and spheres
  • Many specialised forms
  • Homonym with the bone

What robots and AI may and may not do Filled

Must not

  • Confuse radius with diameter in specifications used to build or order parts.
  • Omit units or tolerances when reporting a radius for manufacturing.
  • Present an estimated radius as a measured one.

Only with a human decision

  • Approving dimensions for safety-critical parts.

May

  • Compute and explain radii and related measures with units stated.
  • Check that a radius or a diameter is used consistently in a calculation.

Moral aspects Filled

  • Simple geometric errors can cause failures in pipes, wheels and machines.
  • Learners rely on correct definitions.

Who is affected

  • Engineers and makers
  • Students

Owners Filled

Steward

Nobody: a mathematical concept held in common.

Links to other meta-models Filled

parent

  • Q166154 - registry parent class
  • Q36253 - registry parent class
  • Q7280270 - registry parent class

related

  • line segment - category
  • length - category
  • triangle - circumradius and inradius
  • Reissner-Nordstrom black hole - horizon radii

What else AI and robots need to interact with it Filled

Identity and identifiers required Filled

  • Vercy registry: vr.tr.radius
  • Wikidata: Q173817 (https://www.wikidata.org/wiki/Q173817)

Direct properties not applicable Not applicable

Not applicable

Plane XCT: no invented physical properties.

Recognition optional Filled

  • Centre to boundary
  • Half the diameter
  • The radius bone is a separate anatomical sense
  • Not physical; a length in diagrams and specifications.

Capabilities and actions required Filled

  • compute radii from other measurements
  • explain radius of curvature and specialised radii
  • apply radius in engineering specifications
  • separate the anatomical sense

Hazards and failure modes required Filled

  • Confusing radius and diameter
  • Ignoring minimum bend radius in cables and pipes
  • Confusing senses

Standards and interfaces required Filled

  • ISO 80000-2 and 80000-3 notation
  • Engineering standards for bend radii and fillets

Context of use required Filled

  • Geometry, engineering and physics.
  • radius of circles and spheres
  • radius of curvature
  • engineering radii such as pipe, shaft and bend radii
  • physical radii such as the Schwarzschild radius
  • atomic and ionic radii

Sources Filled

  1. Wikidata item Q173817: radius - identity and sense of the item
  2. Wikipedia: Radius - general description of the item

Open questions

  • Should radius of curvature be a separate entry?
  • How should engineering standards be linked?
  • How should the anatomical sense be split?

Machine files

Card as JSON Specification Card backlog vercy.card/1

Provenance

thing registry research (pass 2) · unreviewed

Built from: models/things/publications/thing-q173817/spec.json