But luckily for us, there's a classical equation of motion that will, in fact, describe how the electron and nucleus change position or change their radius as a function of time.

但幸运的是，有一个,经典方程描述了电子和核子,位置或者它们直接的距离是,如何随时间变化的。

麻省理工公开课 - 化学原理课程节选

You shoot something, you should know when it will land, where it will land, with what speed it will land, how high it will go.

抛出一个物体,我们要知道落地时间,落地位置,还有落地的速度,最高点的高度

耶鲁公开课 - 基础物理课程节选

The work is not, in a sense, written simply as a sort of timeless philosophical treatise, but as a dramatic dialogue with a setting, a cast of characters and a firm location in time and place.

但本书的著作目的，不仅是,永恒的的哲学论述，更是戏剧性的对话，内含场景，人物,及一个确切时间与位置。

耶鲁公开课 - 政治哲学导论课程节选

That is the whole triumph of calculus is to know that by looking at the position now, the position slightly later and taking the ratio and bringing later as close as possible to right now, we define a quantity that we can say is the velocity at this instant.

这就得靠微积分了,通过了解它现在的位置,和一小段时间以后的位置,计算它们的比,再让时间间隔尽可能缩短,我们就定义了一个,被我们称之为瞬时速度的物理量

耶鲁公开课 - 基础物理课程节选

if I say a particle's location is i times t^2 plus j times 9t^3, for every value of time, you can put the numbers in and you can find the velocity by just taking derivatives.

一个质点的位置,i ? t^2 + j ? 9t^3,在每一个时间点,你可以把数值代入,并通过求导得到速度

耶鲁公开课 - 基础物理课程节选