The Effects of Projectile Speed and Medium Resistance in Ricochet off Sand

Abstract

It has been observed experimentally that when a sphere ricochets off water or sand the critical impact angle depends on the impinging velocity. To explain this, a model is developed which takes into account the weight of the sphere and the static resistance of the medium into which penetration occurs. The proposed model can also treat processes in which the angle of impact is large and where the velocity of the sphere undergoes considerable change. Projectile trajectories which have been calculated for various conditions are presented and discussed. Numerical results for steel, aluminium alloy, and lead spheres are in good agreement with such experimental results as are available.