Java SE (Java Platform, Standard Edition)

Does anyone know of a way of creating the realistic motion of an object? Say I have a sphere in my scene and I apply a positionInterpolator to it so that it rises and falls is there any way I can make it decellerate and accelerate according to the law gravity as it would naturally?

If it were possible to apply different increasing alpha ramp durations to the Alpha object it may be possible, but this is not the case.

Any suggestions would be much appreciated,

Nik