free-fall model

例句：

1. 1. The free-fall model is a useful tool for predicting the behavior of objects in motion.
   自由落体模型是一个预测运动物体行为的有用工具。
2. 2.In this model, the particles move freely and their interaction is determined by the forces acting on them.
   在这个模型中，粒子可以自由移动，它们的相互作用由作用于它们的力量决定。
3. 3.The free-fall model has been widely used in engineering to simulate the behavior of materials under various conditions.
   自由落体模型在工程中被广泛使用，以模拟各种条件下材料的行为。