 Special cases of motion described be these equations are summarized qualitatively in the table below.Two have already been discussed above, in the cases that either the radial components or the angular components are zero, and the non-zero component of motion describes uniform acceleration.In 3D space, the equations in spherical coordinates with corresponding unit vectors , and , the position, velocity, and acceleration generalize respectively to

In the case of a constant this reduces to the planar equations above.