perimeter
Let an agent explain perimeter and its computation, relay formulas for common shapes, describe applied forms in hydraulics and anthropometry, and distinguish perimeter from area, circumference and boundary.
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 perimeter and its computation, relay formulas for common shapes, describe applied forms in hydraulics and anthropometry, and distinguish perimeter from area, circumference and boundary.
The total length of the boundary of a two-dimensional shape, such as the sum of the sides of a polygon or the circumference of a circle, and by extension the boundary itself; perimeter is computed by formulas for regular shapes and by measurement or integration for irregular ones, and applied forms include the wetted perimeter of a channel in hydraulics and body circumferences such as waist, hip, bust, neck and calf in anthropometry.
What it is for: Measuring the length around a shape.
It can be explain the concept; compute perimeters; describe applied forms; distinguish from area and other measures.
Distinguishing features
Length measure
Boundary of a region
Formulas for regular shapes
Applied variants
What it looks like
Not a visible object; the outline of a shape.
Physical character
circle circumference: 2 pi r formula
How it is recognised
Length of a boundary
Polygon perimeters, circumferences, wetted perimeter, body circumferences
Area measures the inside; a boundary is the curve itself; a security perimeter is a figurative use
Related models
is a kind of - in registry terms
is a kind of - in registry terms
is contrasted with - the interior measure
is related to - the circle case
In practice
Families and kinds
perimeters of polygons
circumferences of circles and ellipses
wetted perimeter in hydraulics
body circumferences such as waist, hip, bust, neck and calf
perimeters of irregular regions by measurement
perimeter in geometric measure theory
Standards and regulation
ISO 80000-3 for length quantities
Anthropometric measurement standards such as ISO 8559
Hydraulic engineering conventions for wetted perimeter
Failure modes and hazards
Confusing perimeter with area
Unit errors
Inconsistent measurement of body circumferences
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.
Define What perimeter is.
Definition.
Definition
Definition and distinctions.
Definition
Definition.
- What is perimeter, and how does it differ from area, circumference and boundary? definition
- Is the question about geometric perimeter, wetted perimeter or a body circumference? boundary
Formulas
Formulas.
Formulas
Formulas.
- What formulas give the perimeter of common shapes? definition
- Which entry fits the specific shape? action
Compute Computation.
Computation.
Calculate
Calculating perimeter.
Calculate
Calculate.
- How is the perimeter of regular and irregular shapes computed? action
- What is the result for the shape in question? measurement
Ellipse
Hard cases.
Ellipse
Ellipse.
- Why has the ellipse no simple perimeter formula, and how is it approximated? provenance
- Which references are standard? provenance
Applied Applied forms.
Application.
Hydraulics
Wetted perimeter.
Hydraulics
Hydraulics.
- What is wetted perimeter, and how is it used in hydraulic radius calculations? provenance
- Which entry fits hydraulic radius? action
Body
Body circumferences.
Body
Body.
- How are waist, hip and other circumferences measured and used in health and clothing? provenance
- Is the user asking for personal health interpretation, which needs a professional? boundary
Context Theory and teaching.
Context.
Theory
Isoperimetric problems.
Theory
Theory.
- What do isoperimetric inequalities say about perimeter and area? provenance
- Which entry fits isoperimetric inequality? action
Teach
Teaching.
Teach
Teaching.
- How is perimeter taught, and which misconceptions arise? provenance
- Which sources are cited? provenance
What the second pass must settle
- Should wetted perimeter and waist circumference be separate entries?
- How should measurement standards be linked?
- The registry entry has merged aliases naming body measurements; should they be split off?