3柱坐标系中9p10 +-(rm)(m)+-(m2)=0 at r ar r00 4球坐标系中2+10m)+1m如02-1乱m)0 ar sing 00 rsin 0 aB3. 柱坐标系中 ( ) ( ) 0 1 ( ) 1 =   +   +   +   r z v z v r r v t r r       4. 球坐标系中 ( ) 0 sin ( sin ) 1 sin 1 ( ) 1 2 2 =   +   +   +              v r v r r v r t r r