When it's spinning parallel to the ground, support your weight on your left foot and use your right foot to power your spin; the momentum of the hoop should carry you around.
首先从前位站姿开始；让呼啦圈逆时针转起来，当旋转和地面平行的时候，把重心放到左脚上，用你的右脚来给力；呼啦圈的动力会带动你晃动。
Spin angular momentum will start to chase the torque.
旋转的角动量会开始，跟随那个力。
I am the spin angular momentum.
我就是旋转的角动量。
We have here the spin angular momentum that you saw.
这有一个旋转的角动量,如你们所见。
有了旋转的角动量。
So spin angular momentum has the property of stabilizing things.
旋转的角动量有，稳定事物的性质。
You give it spin angular momentum, it becomes stable.
有了一个旋转的角动量，就变得稳定。
Look at that spin angular momentum.
观察那个旋转角动量。
What will the spin angular momentum do?
旋转的角动量会怎样呢？
So this was originally the spin angular momentum of the wheel.
所以，这是原本的旋转的，角动量。
That's a spin angular momentum.
那是旋转的角动量。
The spin angular momentum is now in this direction, so I'm going to give it a torque like so.
旋转的角动量现在是这个,方向的，我给它一个这样的力。
And so the angular momentum of spin of the wheel is in this direction.
所以旋转的角动量是，这个方向。
So the torque is persuading the spin angular momentum to change.
所以力是使得旋转的角动量,改变的理由。
If I put it on this side, torque is now in this direction, spin angular momentum is in this direction.
在这边，力现在就是这个，方向的，旋转角动量是，这个方向的。
And as long as I torque it like this, that spin angular momentum wants to go around in the horizontal plane.
只要我这样使力，旋转的角动量就是想要，水平的转动。
But notice that l, the spin angular momentum, has moved from here to here.
注意l，旋转的角动量，已经从这移到了这。
I've changed the direction of the spin angular momentum.
我改变了旋转角动量，的方向。
If Page's plan isn't to keep the patents and valuable technology and quickly cut the rest, expect pressure for a spin-off to build up momentum over time.
如果佩奇的如意算盘不是仅仅保留专利和宝贵的技术，同时迅速切除其他业务的话，他将面临压力，分拆手机制造业务，待其累积优势，重创辉煌。
And what does the spin angular momentum do?
旋转的角动量怎么了呢？
So this only holds in situations where the spin angular momentum is way, way larger than the angular momentum that you get due to the precession.
所以成立的情况是，旋转的角动量，比旋进的角动量要，大很多很多才行。
So the torque will also change direction and so this angular momentum, spin angular momentum will keep chasing the torque and start to rotate freely.
所以力也会改变方向,这个角动量，角动量会保持追着力,并开始自由地转动。
I'll give it a little bit more spin angular momentum, so now I move my left hand towards me and my...
我再给它多一点的角动量，现在我将我的左手朝我移动。
I'm going to spin it with a high angular momentum, high spin angular momentum.
以高的角动量来旋转，高旋转的角动量。
Angular momentum has two key components: spin angular momentum and orbital angular momentum.
角动量有两个分量：自旋角动量和轨道角动量。
Absorption of the light allows both the spin and orbital angular momentum of a light beam to be transferred to microscopic particles held within optical tweezers, forming an optical spanner.
光的吸收可以同时导致光束的自旋角动量或轨道角动量转移给微米粒子，就像光学镊子一样引起粒子的转动，从而形成光学扳手。
Unlike Einstein's equations, ECKS gravity takes account of the spin or angular momentum of elementary particles.
不同于爱因斯坦的方程，ECKS万有引力理论考虑了基本粒子的旋转或角动量。
This article reviews the physics of angular momentum transfer and loss in optical pumping and spin-exchanging collisions.
评述了光抽运和自旋交换碰撞中角动量转移和损失的物理。
VIRW is a new momentum exchange device, which can provide attitude control torque not only by adjusting the spin rate, but also by changing the inertia of the wheel.
变惯量反作用飞轮是一种新型的动量交换装置，不仅可以通过改变飞轮转速输出力矩，还可以通过改变其转动惯量实现大范围的力矩输出。
Longitudinally polarized electrons are the electrons with spin and momentum pointing in the same direction.
纵向极化电子，就是自旋和动量方向相同的电子。
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