1. The problem statement, all variables and given/known data A pile driver of mass 220 kg is allowed to fall from rest through a distance of 1.8m on to a 380 kg concrete pile to drive it into the ground. Each impact drives the pile into the ground by 200 mm. Assuming that the pile driver remains in contact with the pile after impact and that momentum is conserved, use the principle of conservation of energy to calculate b. The change in potential energy of the driver and pile combination on moving into the ground. 2. Relevant equations b. Conversion of potential energy into kinetic energy 3. The attempt at a solution No attempt made as of yet as I am struggling to understand the question. I am assuming that tp work this out two parts are required; Fist calculate potential energy for driver = 220*9.81*1.8 = 3884.76 joules Then calculate potential energy of the pile - which is either= 380*9.81*-20 or 380*9.81*20 (I am unsure of the 20mm if it easier positive or negative with being driven into the ground, but the direction of force is the same) Then calculate the difference and convert to kinetic energy. Any help would be really appreciated. I am not looking for the exact workings out, but a point in the right direction. Thanks in advance!