time interval principle

例句：

1. 1.The principle of conservation of energy is fundamentalto the development of modern technology.
   能量守恒原理是现代科技发展的基础。
2. 2. Inthis experiment, we applied the principle oflever action to demonstrate the relationship between forceand displacement.
   在这个实验中，我们应用了杠杆原理来展示力和位移之间的关系。
3. 3.The principle of proportionality is crucialin determining the efficiency of a machine.
   比例原则在确定机器效率方面至关重要。