Newton's Law of Gravitation Calculator mechanism

Model scope

The algebraic formula is correct, but the specification is incomplete because input units, the exact numerical value/version of G, the center-to-center meaning of r, and the valid spherical-body domain are not stated. The honest label should say that the instrument returns gravitational-force magnitude in newtons under SI-unit assumptions, not a force vector; 'n/a' is insufficiently informative.

• F=Gm1m2/r² is the standard magnitude formula for two point masses, or for appropriately separated spherically symmetric bodies, but the specification does not constrain spherical bodies to cases where this simplification is valid; it is not generally valid for arbitrary overlapping finite spheres.
• The output is only force magnitude. A direction or vector is not computed, so the instrument should not label the result as a complete force vector.

Units and conventions

• m1 and m2 must be masses in kilograms (kg).
• r must be center-to-center separation in meters (m), not surface-to-surface separation.
• F is returned in newtons (N).
• Use G=6.67430×10^-11 N·m²/kg², explicitly identifying the CODATA release or numerical constant used.
• Inputs should satisfy m1≥0, m2≥0, and r>0; ordinary physical masses are strictly positive.

Inspectable vector

One of 4 source-bound review vectors:

{
  "inputs": {
    "m1": 5,
    "m2": 10,
    "r": 2,
    "mass_unit": "kg",
    "distance_unit": "m"
  },
  "expected_outputs": {
    "F_N": 8.342875e-10
  },
  "working": "F=Gm1m2/r²=(6.67430×10^-11)(5)(10)/(2²)=(6.67430×10^-11)(50)/4=(6.67430×10^-11)(12.5)=8.342875×10^-10 N."
}

Failure boundary

BREAK_CLAIMED · SELF_FLAGGED

The specification omits input units, allowing a plausible centimetre-versus-metre interpretation that changes the result by a factor of 10000. The calculator must also reject r = 0 rather than return a numeric result. No actual formula branch exists to switch.

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
• BOUNDARY_HAZARD_CATALOG.json