This has absolutely no tangential velocity.

这绝对没有切向速度。

Her connection to this case is tangential, at best.

她与本案最多也就是一点间接牵涉而已。

Let's start with why is it a big deal to make it… stay tangential.

让我们首先谈谈为什么让它… … 保持切线是一件大事。

But we can also describe an object's rotation in terms of its tangential velocity.

我们也可以一半 以切向速度表示物体的旋转。

In fact, its tangential velocity will be equal to its angular velocity, times the radius.

事实上，它的切向速度将是 等于它的角速度乘以半径。

Because, to get its total velocity, you add the translational velocity to the tangential velocity.

因为要找到它的总速度，我们添加 过渡速度到切向速度。

So, like linear velocity, tangential acceleration depends on the distance between the point and the center of the object.

因此，与线速度一样，切向加速度取决于点与物体中心之间的距离。

And we know that in general, the magnitude of tangential velocity is also equal to the radius, times the angular velocity.

而我们知道，一般情况下，切向速度的大小也等于半径乘以角速度。

Because at the bottom of the wheel, the tangential velocity is pointing opposite to the direction the wheel is rolling in.

因为在轮子底部，切向速度表示 反转车轮运动的方向。

But there’s also tangential acceleration, which describes whether an individual point on a rotating object is speeding up or slowing down.

但也有切向加速度，它描述了旋转物体上的单个点是在加速还是在减速。