density that is the first derivative of the inverse material ratio Pcm(c), Wcm(c), Rcm(c) at a given level c of intersection, tihedus, mis on materjali pöördsuhte Pcm(c), Wcm(c), Rcm(c) esimene tuletis antud lõikepunkti/-sirge c juures

density that is the first derivative of the inverse material ratio Pcm(c), Wcm(c), Rcm(c) at a given level c of intersection, tihedus, mis on materjali pöördsuhte Pcm(c), Wcm(c), Rcm(c) esimene tuletis antud lõikepunkti/-sirge c juures