How to get top left coordinate when the coordinate on circumferenceofcircle is known?
如何获得左上坐标在圆周圆的坐标是已知的？
2
And that linear velocity, which, in this case, is really your speed, is of course the circumferenceof 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。
3
That point falls on the circumferenceof the circle.