free-running frequency

• 自然频率,固有频率

free-running frequency的用法和样例：

例句

1. The natural frequency of specimen decreases as the crack length increases.
   随着裂纹长度的增加，试样的固有频率逐渐减小。
2. The swing is a pendulum with a single natural frequency depending on its length.
   秋千是只有一个固有频率的摆，此频率决定于它的长度。