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Published

angular measure

vr.tr.angular-measure · thing-q1357788

Let an agent explain angular measures by unit, conversion, measurement and application in mathematics, physics, navigation and astronomy.

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

Units Which unit.

Convert

Conversion.

Convert

Conversion.

  1. What is this angle in radians or degrees? measurement
  2. How precise must it be? boundary

Small angles

Arcminutes and arcseconds.

Small angles

Small angles.

  1. How are arcminutes and arcseconds used? definition
  2. What is this in decimal degrees? measurement
Measure Instruments.

Instrument

Tools.

Instrument

Instruments.

  1. Which instrument measures this angle to the required accuracy? provenance
  2. How is it calibrated? provenance

Convention

Direction and sign.

Convention

Conventions.

  1. Is the angle measured clockwise or anticlockwise, and from which reference? definition
  2. How are negative angles treated? definition
Mathematics Trigonometry.

Trigonometry

Functions.

Trigonometry

Trigonometry.

  1. What are the sine, cosine and tangent of this angle? measurement
  2. Is the calculator in degree or radian mode? boundary

Radian

Why radians.

Radian

Radians.

  1. Why are radians natural in calculus? definition
  2. How is a radian defined? definition
Applications Uses.

Navigation

Bearings.

Navigation

Bearings.

  1. How are bearings expressed in navigation? definition
  2. What is the difference between true and magnetic bearings? definition

Astronomy

Angular size.

Astronomy

Angular size.

  1. What is the angular size of this object in the sky? measurement
  2. How does it relate to distance and size? definition

Classifiers Filled

Family
Thing Registry
Category
Cross-cutting context
Entry kind
thing
Plane
XCT
Domain
XCT.QLT
Other names and narrower kinds
phase angle, angular displacement, angular difference, initial phase, Bragg angle, scattering angle, polar angle, angle between two vectors, angle of internal friction, phase angle of voltage, phase angle of electric current, grazing angle

What it is Filled

A measure of the size of an angle or of a rotation, expressed in units such as the radian (the SI unit), degree, gradian, turn and arcminute or arcsecond; a full turn equals 360 degrees or 2 pi radians, and related quantities include phase angle and angular displacement.

Why it exists Filled

Let an agent explain angular measures by unit, conversion, measurement and application in mathematics, physics, navigation and astronomy.

Distinguishing features Filled

  • Measures rotation or opening
  • Radian is dimensionless in SI
  • Many units
  • Used across sciences

What robots and AI may and may not do Filled

Must not

  • Mix degrees and radians silently in calculations that control machines or navigation.
  • Round angles in a way that hides errors relevant to safety.
  • Present an angle without its unit where it could be misread.

Only with a human decision

  • Changing angular settings on machinery, antennas or vehicles that people rely on.

May

  • Convert and report angles between units with stated precision.
  • Check that angular inputs to calculations use the expected unit.

Moral aspects Filled

  • Unit confusion in angles has caused failures in engineering and navigation.
  • Shared units let people across fields and countries check each other's work.

Who is affected

  • Engineers and navigators
  • People relying on systems built with these measures

Owners Filled

Steward

Nobody owns it; the international metrology bodies define the SI unit.

Links to other meta-models Filled

parent

  • Q121960184 - registry parent class
  • Q123410660 - registry parent class

related

  • geometric measure - category
  • radian - unit
  • trigonometry - field
  • protractor and theodolite - instrument

What else AI and robots need to interact with it Filled

Identity and identifiers required Filled

  • Vercy registry: vr.tr.angular-measure
  • Wikidata: Q1357788 (https://www.wikidata.org/wiki/Q1357788)
  • SI unit: radian (rad) plane angle

Direct properties not applicable Not applicable

  • full turn: 360 or 2 pi degrees or rad - exact

Plane XCT: no invented physical properties.

Recognition optional Filled

  • Symbols such as deg, rad and arcsec
  • Protractors and theodolites
  • Slope as a percentage is a different measure
  • Not physical; shown on protractors, dials, compasses and in formulas.

Capabilities and actions required Filled

  • convert between degrees, radians and other units
  • measure angles with instruments
  • use angles in trigonometry and physics
  • read angular sizes in astronomy

Hazards and failure modes required Filled

  • Mixing degrees and radians in calculations
  • Sign and direction conventions

Standards and interfaces required Filled

  • SI Brochure (BIPM)
  • ISO 80000-3 space and time quantities

Context of use required Filled

  • Describing angles and rotations.
  • plane angles
  • solid angles (steradian)
  • phase angles
  • angular displacement
  • angles of scattering and diffraction

Sources Filled

  1. Wikidata item Q1357788: angular measure - identity and sense of the item
  2. Wikipedia: Angular distance - general description of the item

Open questions

  • Should units be separate entries?
  • How should solid angle be linked?
  • How should navigation bearings be linked?

Machine files

Card as JSON Specification Card backlog vercy.card/1

Provenance

thing registry research (pass 2) · unreviewed

Built from: models/things/publications/thing-q1357788/spec.json