math displaystyle math usage typical lagrangian mechanics radius vector math displaystyle mathbf r math expressed definite function math displaystyle q ldots q n math vector function resolves constraint equations sense upon substituting equations fulfilled identically math displaystyle q ldots q n math internal presentation velocity vector velocity vector constrained newtonian dynamical system expressed terms partial derivatives vector function numblk math displaystyle mathbf v sum n frac partial mathbf r partial q dot q math quantities math displaystyle dot q ldots dot q n math called internal components velocity vector sometimes denoted
Natural science Physics Newtonian dynamics