As it did, angular momentum became important.

随着它的坍缩，角变得重要起来。

That's called conservation of angular momentum.

这称为「角守恒定律」。

But the original star's angular momentum is preserved.

但原始恒星的角被保留了下来。

What's neat is that they can maintain angular momentum indefinitely.

最酷的是它可永久性地保持角。

It's a physics toy that demonstrates angular momentum, potential energy, and kinetic energy.

是个物理学家的玩具可演示角还有能和势能。

Since the angular momentum doesn't change, when the distance increases the velocity has to decrease.

由于角不变，当距离增加时，速度就会减小。

More angular momentum means she can make more turns before needing to replenish what was lost to friction.

更多的角意味着 她可转更多圈 ──在因摩擦力损失，需再补充之前。

Take quantum vortices, which are basically whirlpools of angular momentum in materials like superconductors and superfluids, giving them strange properties.

子涡旋为例，它基本上是超导体和超流体等材料中角的漩涡，使它们具有奇特的性质。

And except for what's lost to friction, that angular momentum has to stay constant while the dancer is on pointe.

除了摩擦损耗的之外，当舞者踮起脚尖时 角必须保持不变。

That's called the conservation of angular momentum.

- 这就是所谓的角守恒。

Well, as a planet orbits the Sun it may not keep a constant speed but it does maintain its angular momentum.

当行星绕太阳运行时，它可能不会保持恒定的速度，但它的角会保持不变。

So the approach we chose to use is angular momentum.

所我们选择使用的方法是角。

And that factor is angular momentum.

斜率，那个因素就是角。

And, like linear momentum, angular momentum is always conserved.

和线性、角一样 一直得救。

By bending in the middle and using fast twitch muscle fibers, they can whip around without ever changing their net angular momentum.

透过在身体中断弯曲并使用快肌纤维，它们可在不改变其净角的情况下摆。

In physics, angular momentum describes something’s tendency to stay rotating once it’s started.

在物理学中， 角描述了某物一旦开始就保持旋转的趋势。

The Dirac Equation accurately predicted the behavior of electrons, including their intrinsic angular momentum or " spin, " which had been perplexing scientists.

狄拉克方程准确地预测了电子的行为，包括它们的固有角或“自旋”，这一直困扰着科学家。

This is because of a principle called conservation of angular momentum.

这是因为称为角守恒的原理。

You can't create or destroy angular momentum. It always has to go somewhere.

你不能创造或破坏角。 它总是必须去某个地方。

So their rotation speed slows down to compensate and keep their angular momentum the same.

因此它们的旋转速度减慢补偿并保持它们的角相同。