equivalent equation

例句：

1. 1. In the context of thermodynamics, an equivalent equation is used to describe the relationship between two substances.
   在热力学中，使用等价方程来描述两种物质之间的关系。
2. 2. The researchers developed an equivalent equation that could accurately predict the behavior of the material under various conditions.
   研究人员开发了一个等价方程，可以准确预测材料在不同条件下的行为。
3. 3. The engineer used the equivalent equation to calculate the stresses in the beam, which helped to optimize the design.
   工程师利用等价方程计算了梁中的应力，这有助于优化设计。