Center of Mass Calculator 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

t4-239

Effect

Computation or source lookup only

Input and validation requirements

The all-zero-mass input makes the denominator vanish and the result undefined. Because the specification does not state validation behavior, a plain arithmetic implementation could emit NaN instead of rejecting the input. The formula also has no actual piecewise branch, so the branch-switch requirement is not applicable beyond confirming that the same formula is used.

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": {
    "masses_positions": [
      {
        "mass": 2,
        "position": [
          0,
          0
        ]
      },
      {
        "mass": 3,
        "position": [
          5,
          0
        ]
      }
    ],
    "mass_unit": "kg",
    "position_unit": "m"
  },
  "expected_outputs": {
    "r_cm": [
      3,
      0
    ],
    "position_unit": "m"
  },
  "working": "Total mass = 2 + 3 = 5 kg.\\nX numerator = (2×0) + (3×5) = 0 + 15 = 15 kg·m.\\nY numerator = (2×0) + (3×0) = 0 + 0 = 0 kg·m.\\nCOM = (15/5, 0/5) = (3, 0) m."
}

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