经研究，发现地极还存在长期的漂移和周期约30年的长周期摆动。

The study found that there are still a long-term polar drift and cycle of about 30 years of long-period oscillation.

youdao

这是摆动的周期吗？

So what is the period of oscillation?

youdao

我只需要带去这个等式，我想知道这跟，摆动杆的周期。

I simply go to this equation, and I want to know what the period is of this rod, of this oscillating rod.

youdao