In cartesian coordinates dr= dx i+dy j+ dzk dr dx dv dz +=j+,k dtdt dt The vector v can also be written in terms of its components as: v=vi+vi+vk dy Vx dt vy dt v: dt (2-12)   = = + + k dt dz j dt dy i dt dx dt dr v   The vector can also be written in terms of its components as: (2-11) v  v v i v j v k x y z     = + + dt dx vx = dt dy vy = dt dz vz = (2-12)    dr = dx i+ dy j+ dz k  In cartesian coordinates: