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Collision dynamics

Restitution and Delta-V Calculator

Account for rebound when a collision model requires a supported coefficient of restitution.

Method overview

restitution = relative separation speed ÷ relative approach speed

Restitution is most influential in lower-speed impacts where rebound is a meaningful share of the total velocity change. The worksheet keeps the assumed coefficient visible in the result.

Evidence to document

  • A collision model consistent with the impact geometry.
  • Supported vehicle masses and velocity directions.
  • A coefficient derived from relevant testing or case evidence.
  • Separation evidence when it can be measured directly.

Limitations

Do not select a coefficient simply to make another result fit. Vehicle structure, overlap, speed, and impact configuration affect restitution.

Record measurements, assumptions, units, rounding, and source material so another investigator can reproduce the result. See the methodology and validation center for verification policy and citation guidance.

Related tools

Delta-V · Crush energy · Momentum