I'm writing a real time 3D physics simulator that simulate bullet ballistics. Can I use the air drag formula that factors in drag coeficient and outputs drag force to calculate how deep a bullet will penetrate a target material? Say I substitute air pressure with target material density. And then I can use the drag force to calculate when the bullet will come to a full stop and the distance travelled. (The force of the bullet would have to be over the tensile compression strength of the material to travel in the material medium or else I will have to assume the bullet bounced off it.) That would work right? Furthermore I could also use the drag force to work out energy due to air friction and increase the heat of the material and the bullet to make the computer simulation decide if the bullet or the target material is hot enough to melt and therefore change properties in density. But how do I decide what percentage of air friction goes into the bullet vs the target medium? In fact for a bullet travelling in air, how does the heat dissipate? 50:50 between bullet and air?