1. The problem statement, all variables and given/known data I am trying to model an impact between a solid and a liquid as a 1D elastic collision where KE and momentum are conserved. Calculating the impulse is no problem. My problem in when I try to come up with an accurate collision time in order to calculate impulsive forces. Does anyone know of a reasonably accurate approach to find these forces. 2. Relevant equations Conservation of KE, Conservation of Momentum, Herztian correlations for impacting solids, elastic coefficients of impacted materials. 3. The attempt at a solution Use Hertzian correlations between two elastic solids to get an idea of the impact time (around .003s) for my initial conditions.