1D/2D Inelastic Collision Solver (coefficient of restitution) 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

t4-215

Effect

Computation or source lookup only

Input and validation requirements

Zero total mass causes division by zero and an underdetermined collision, so the solver must reject that input. The e>1 branch is also outside the stated physical domain and must be rejected rather than silently treated as an ordinary inelastic collision.

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": {
    "m1": 2,
    "m2": 3,
    "v1": 5,
    "v2": -1,
    "e": 0.5,
    "mass_units": "kg",
    "velocity_units": "m/s"
  },
  "expected_outputs": {
    "v1_prime": -0.4,
    "v2_prime": 2.6,
    "energy_lost": 16.2
  },
  "working": "M=m1+m2=2+3=5. Initial momentum p=2(5)+3(-1)=10−3=7. Initial relative velocity v1−v2=5−(−1)=6. Final relative velocity v2'−v1'=e(v1−v2)=0.5(6)=3. Solve v1'=(p−m2·3)/M=(7−3·3)/5=(7−9)/5=−0.4. Solve v2'=v1'+3=−0.4+3=2.6. Initial KE=0.5(2)(5²)+0.5(3)((−1)²)=25+1.5=26.5 J. Final KE=0.5(2)((−0.4)²)+0.5(3)(2.6²)=0.16+10.14=10.3 J. Energy lost=26.5−10.3=16.2 J."
}

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