等效位能是将许多效应综合成单一位能的数学表达式。在古典力学中，等效位能即为离心力位能与位能的和。等效位能常被用来计算行星的轨道及半古典的原子计算，可用来降低问题的维度。

等效位能 可定义如下：

L 为角动量。

r 为两物体之距离。

m 为绕行物体之质量。

U(r) 为位能。

等效力，也就是等效位能的梯度取负号则为：

其中 为r方向的单位矢量。

The effective potential (also known as effective potential energy) is a mathematical expression combining multiple (perhaps opposing) effects into a single potential. In classical mechanics it is defined as the sum of the 'opposing' centrifugal potential energy with the potential energy of a dynamical system. It is commonly used in calculating the orbits of planets (both Newtonian and relativistic) and in semi-classical atomic calculations, and often allows problems to be reduced to fewer dimensions.