But this wheel isn’t slipping -- its bottom has a total velocity of zero, because its velocities cancel out.

但是这个轮子并没有打滑——它的底部总速度为零， 因为它的速度相互抵消了。

But this wheel isn't slipping -- its bottom has a total velocity of zero, because its velocities cancel out.

但是这个轮子不打滑，低于它的速度 大学是不存在的，因为它的速度相互抵消。