A falling object gains momentum as it falls.

下落的物体下落时增加。

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

是个物理学家的玩具可以演示角还有能和势能。

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

以子涡旋为例，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。

Even a 20-minute daily walk can make a big difference.

就算每天的运是20分钟的散步 也能让你有巨大的改变。

And the more you do, the better.

运越大，好越多。

According to studies, its activity during sleep is even higher than during the day.

根据研究，睡眠时大脑的活甚至比白天还。

You can get the motion down and then it puts less strain on your back.

你可以减少运，这样可以减少对背部的压力。

Do you exercise much, Phil? I try to. I ride my bike at the weekend. But to be honest I do spend a lot of time sitting down.

菲尔，你运多吗？我努力多锻炼，周末骑自行车，但说实话，大多数时间我确实都是坐着的。

These activities are small but definite steps toward losing weight.

这些活虽然运不大，但都是减肥的必步骤。

As mentioned earlier, you should enter ketosis sometime within the first 3 days or so of fasting, and it depends on how much you are moving around and what your diet was like before starting the fast.

正如之前提到的，有时你应该会在在禁食的前三天内进入酮症，而这取决于你断食前的活和饮食习惯。

That decreased activity corresponded with roadblocks to speech delivery.

这种活减少与说话时的障碍相对应。

It is, by far, the most athletic two minutes of my entire life.

这是迄今为止我人生中运最大的两分钟。

How much exercise do I really need to do?

我究竟需多大的运？

It's about physics and momentum rather than a strike.

它是关于物理、，而不是击倒对方。

Study subjects were grouped according to the amount of activity they reported.

根据研究对象的活将其进行分组。

You might have to cut down on the amount of exercise or sport you do.

你可能不得不减少你的运或体育活。

Or maybe that the level of physical activity just isn't the best idea.

或者也许增加运并不是什么好主意。

That was the most work per acre of any fire he was ever on.

在他经历过的火灾中，那场是每英亩劳最多的。

An easy way to think about this is it's called momentum transfer.

一个简单的理解方法，这是传递的结果。

And it's important to get the right dose of activity.

掌握合适的运也很重。