Public evidence

physics.fluid.drag

Machine-checked verification for calculation version 1.0.0 · tier engine_tested

Open calculator API Capability Download JSON CVP Manifest MCP Review policy

CVP: CVP VERIFIED · CVP protocol 1.0.0-proposed · Engineering assurance· Quadratic drag · Protocol · Schema · Production report

Declared partition coverage: PASS · 2/2 declared partitions (drag, invalid-domain)
Versions: Calculation 1.0.0 · CVP protocol 1.0.0-proposed
CVP identity: 1/1 property · digest a035954e5fab

Verification

Legacy regression suite: 3/3 calculation tests · Production surface contract 4/4

Three distinct suites: educational examples on the calculator page, this legacy regression count (3/3 golden + boundary), and the CVP verification suite below. They are not the same number. Property, metamorphic, round-trip, O3, and interface statuses/checks are recorded in the CVP Manifest . SKIP (0/0) means that suite has no published vectors.

This calculator CURRENT · Public schema 1.0.0 matches · Semantic contract ✓ · Production attested · Public/cache ✓ · Origin ✓

CVP verification suite

Protocol checks from the Evidence Manifest. Distinct from the legacy regression suite above. Calculation version 1.0.0. CVP 1.0.0-proposed. 1/1 golden · 1/1 CVP boundary · 1/1 invalid · 1/1 property · 1/1 cross-interface · 1/1 CVP contract. digest a035954e5fab.

Golden (oracle-backed) 1 / 1
CVP boundary 1 / 1
Invalid input 1 / 1
Property 1 / 1
Cross-interface 1 / 1
CVP contract 1 / 1
Interfaces PASS · UI (SSR) / REST / MCP
Interface claim ui-ssr is query-result HTML, not a live browser session.
Assurance Engineering

release artifacts aligned PASS
schema valid input executes PASS
engine success output validates schema PASS
schema rejects incomplete input PASS

Fingerprint sha256:74cb3ecf524350346605d16ad5c803b928e0bc7212aa22f5b9157977045b92d5

Input schema sha256:284dba8895050bd204f37c9bc54a36d211e077dd059c8a29c50180e2348fffd5 · Output schema sha256:7ade1aa53957cb4a24ad110b4b46b963124788a83d4049ff26292085c29085b9 · Build-time SHA-256 digests prove published artifacts agree with each other (release_integrity.scope=workspace). Production attestation GETs canonical URLs twice (public/cached view and origin), including Capability HTML, via npm run attest:production --write (published at /.well-known/calculatorx-production-attestation.json) and fails if the public Capability page advertises a different calculation_version. This is artifact consistency, not an independent immutable release log.

Build & scope

Engine identity and declared limitations.

Tool: drag
Engine: drag
Engine build: 2026-09-10
Evidence core: 2026-09-10T22:48:17.762Z
Rendered: 2026-09-16T22:03:43.765Z
Last reviewed: —

Limitations

Quadratic drag model; Cd treated as constant

Sources

Standards and references supporting this tool specification. Methods are listed separately — they are algorithms, not bibliographic sources.

Intro physics / NIST units — standard relations
Supports: engine formulas
ISO 80000-4 / fluid mechanics practice — Quadratic drag
Supports: Fd = ½ ρ v² Cd A

Legacy published checks

Golden and boundary cases from the legacy Evidence JSON. CVP property, metamorphic, round-trip, O3, and interface statuses/checks are recorded in the Manifest — including SKIP when a suite has no vectors.

ID	Kind	Status	Detail
`fd`	golden	pass	Expected Fd_N=61.25000000000001 · Actual mode=Fd · rho_kg_m3=1.225 · A_m2=0.5 · v_m_s=20 · Cd=0.5 · Fd_N=61.25
`bad`	boundary	pass	Expected VALUE_MUST_BE_POSITIVE · Actual VALUE_MUST_BE_POSITIVE
`property-drag-cd`	property	pass	0.5