And in terms of equations that we use, it's sometimes easier to plug in the fact, since momentum is equal to mass times velocity.

在我们使用方程这方面，事实上有时是很容易代入的，因为动量等于质量乘以速度。

麻省理工公开课 - 化学原理课程节选

This machinery is so precise that a human hair couldn't even pass between the heads and spinning platters, yet it all works in terrific speeds.

这些设备是很紧密的以至于人的头发,都不能在头和旋转的磁盘之间通过，尽管如此，它的运行速度非常快。

哈佛公开课 - 计算机科学课程节选

and we like log algorithms, because they're really fast. A typical characteristic of a log algorithm is a pro-- or sorry, an algorithm where it reduces the size of the problem by a constant factor.

并且我们也很喜欢对数算法,因为它很快,对数算法的典型特性是高速，哦，抱歉，是他能以常数因子的速度,降低问题的大小，很明显。

麻省理工公开课 - 计算机科学及编程导论课程节选

It's useful to have the average acceleration, which you can find by taking similar differences of velocities.

平均加速度也是很有用的,你可以用类似方法,取速度的变化量求出来

耶鲁公开课 - 基础物理课程节选

And there are various forces that play in the nucleus that will dictate when this will be stable and when it won't be.They isolated it, but it decays very quickly on the order of microseconds Lifetime on the order of microseconds.

在原子核中有很多种力,都会产生作用，当条件是稳定的,还有当它不是的时候，它们提取出来，但是它会以微秒的速度衰变,生命只有几微秒长。

麻省理工公开课 - 固态化学导论课程节选

And so if I have concerns, it is sort of more indirect directions I think economic growth is doing all right, it's doing quite all right, 8% and if it's not 9%, if it's 8% ,7% range that's very handsome economic growth rate that should not be weigh upon anybody's mind as a matter of concern.

如果要说我关心什么，那就是隐藏的经济发展方向,我觉得印度的经济增长很不错，增长势头良好，即便不是9%，也是7%到,这种经济增长速度已经很厉害了,这种情况谁都不应该,表示担心。

普林斯顿公开课 - 国际座谈会课程节选

Light travels basically a foot in a nanosecond. Simple rule of thumb.

光行进的速度是每纳秒一英尺,很简单的经验法则了。

麻省理工公开课 - 计算机科学及编程导论课程节选

So it's useful to have the average velocity.

平均速度还是很有用的

耶鲁公开课 - 基础物理课程节选