G Shock of a sphere in freefall

A lead sphere, initially in mechanical and thermal equilibrium with the atmosphere, falls from an altitude Z1 on a plane located at the altitude Z2. The sphere is submitted to the following processes: 1-2: freefall from state 1 to state 2, defined just before the shock, 2-3: sudden stop due to the shock against the plane, from state 2 to the final state 3.