zero cross level

例句：

1. 1.The zero cross level is the point where two forces are equal in magnitude and opposite in direction.
   零交点水平是两个力在大小上相等、方向上相反的点。
2. 2.The zero cross level is a critical point in the motion of a particle.
   零交点水平是粒子运动中的一个临界点。
3. 3. The zero cross level is used to determine the position of a particle in space.
   零交点水平用于确定粒子在空间中的位置。