d a dt do dr xF+而× dt dδ ×F+而×（而×F) 或 dt a=r,+r⑩en=a,+ann dt dv a    = r ( r) dt d      =  +     或 dt dr r dt d     =  +   ( r) dt d   =   t t n n a e a e   a r et r en = +   2  =  + 