Local Gravitational Acceleration at Altitude implementation

Binding contract

This record describes what an executable surface must bind and validate. It does not claim that a public calculator, package, or production route is deployed.

Record owner

Guth Instruments

Lifecycle

verified-clean

Evidence ID

t4-083

Effect

Computation or source lookup only

Input and validation requirements

The specification exposes a hard undefined-result trap at h=-R and a significant unit-convention hazard for an unlabeled altitude. A correct implementation must reject R+h=0 and require explicit altitude units; it must also reject negative altitudes if the stated above-surface domain is enforced.

Required corrections

No binding erratum is attached to this unique-name record. Implementers must still preserve the declared units, domain, and failure behavior.

Inspectable interface fixture

The sample below is evidence for interface and validation tests, not a production implementation.

{
  "inputs": {
    "body": "Earth",
    "M_kg": 5.9722e+24,
    "R_m": 6371000,
    "altitude_m": 0,
    "G_m3_kg_s2": 6.6743e-11
  },
  "expected_outputs": {
    "g_m_s2": 9.820302,
    "percent_vs_surface": 100
  },
  "working": "GM=(6.67430e-11)(5.9722e24)=3.986025446e14 m^3/s^2. r=R+h=6.371000e6+0=6.371000e6 m. r^2=(6.371000e6)^2=4.0589641e13 m^2. g(h)=3.986025446e14/4.0589641e13=9.820302 m/s^2. g(0)=9.820302 m/s^2, so percent=100*(9.820302/9.820302)=100.0000%."
}

Other records

Sources and evidence

These pointers bind the page to evidence. They do not grant authority or collapse verification into deployment.

• VERIFIED_LEDGER.json
• evidence-tranche4/tranche4-results.json