And that linear velocity, which, in this case, is really your speed, is of course the circumference of the circle divided by how many seconds it takes to go around.

线速度，在这个例子里，就是速率，是这个圆环的周长，除以走一圈，需要的秒数。

youdao

That point falls on the circumference of the circle.

那一个点落在这圆的圆周线上。

youdao

As our circle of knowledge expands, so does the circumference of the unknown. We are now facing.

当我们的知识之圆扩大之时，我们所面临的未知的圆周也一样。䓅。

youdao

It's as a philosopher once imagined: a circle of which the center is everywhere and the circumference is nowhere.

FORBES: Wireless Everywhere