Spherical polar coordinates dr-dx dy dz Z r2 sin0dr dedo e(reo) X=rsinθcoso y=rsinθsino z=rcosθ V= -(Ze)e X r>distance from origin. r=vx2+y2+22 0>angle drop from the z-axis. φ→angle from the x-axis(onx-y plane) c0s0= (xy,z）→(c,0,φ) Vx2+y2+22 Ψ(X,y,Z）→ΨC,0,) tgo=y/x Ψ，0，φ)=R(0)⊙(0)Φ（φ） Spherical polar coordinates 2 2 2 r  x  y  z (x,y,z)  (r, ) x,y,z  r,  r,  R  r r  distance from origin.   angle drop from the z-axis.   angle from the x-axis (on x-y plane) 2 2 2 cos x y z z     tg  y / x d = dx dy dz = r2 sin  dr d d