S5-3直角坐标法运动方程Mx = x(t)12y=y(t)az = z(t)直角坐标与矢径坐标之间的关系r(t) = x(t)i + y(t)j + z(t)k
直角坐标与矢径坐标之间的关系 r t x t i y t j z t k ( ) ( ) ( ) = + + ( ) 运动方程 ( ) ( ) ( ) x x t y y t z z t = = = §5-3 直角坐标法
r(t) = x(t)i + y(t)j+ z(t)kdr-dxi++j+k=vi+vj+vk速度dtdtCMdx文1z业dz2dt
d d x x v t = d d y y v t = d d z z v t = d d d d d d d d x y z r x y z v i j k v i v j v k t t t t 速度 = = + + = + + r t x t i y t j z t k ( ) ( ) ( ) = + + ( )