principle of equilibrium

例句：

1. 1. Theprinciple of equilibrium states that in a system, the forces acting on each object must be equal and opposite.
   平衡原理指出，在一个系统中，作用于每个物体的力必须相等且相反。
2. 2. In the field of economics, the principle of equilibrium is crucial for understanding how markets adjust to changes in demand and supply.
   在经济学领域，平衡原理对于理解市场如何调整对需求和供给的变化至关重要。
3. 3. The principle of equilibrium is often used in environmental science to describe how ecosystems maintain their stability through interactions between species.
   平衡原理常用于环境科学中，描述生态系统通过物种之间的相互作用来维持其稳定性。