Some powerful force inside me made me test my mind.

VOA: special.2009.11.15

They didn't force me into it, but they didn't force me into math, either.

他们不强迫我表演，也不强迫我学数学。

演技要磨练出来 - SpeakingMax英语口语达人

So, we just talked about the force law to describe the interaction between a proton and an electron. You told me that when the distance went to infinity, the force went to zero. What happens instead when the distance goes to zero? What happens to the force?

我们刚刚讨论了描述质子,和电子之间相互作用力的定律,当距离变为无穷时,力变为零，那当距离变为,零时会发生什么？,这时候力是多少？

麻省理工公开课 - 化学原理课程节选

And it's our country's national force and I live in a great country so it's an honor for me to serve here."

VOA: standard.2010.02.25

You cannot say to me, "Take a force, due to a spring, and see what force it applies and divide by the acceleration and get the mass, " because we haven't defined force, either.

你不能说,"给弹簧施加一个力,看看它能提供多大的力,然后除以加速度,得到质量",因为我们还没给力下一个定义

耶鲁公开课 - 基础物理课程节选

That's how by either balancing the unknown force with a known force or by simply measuring the acceleration as I fall towards this podium and multiplying by mass, you can find the force that exerts on me.

我们既可以让未知力与已知力平衡,也可以只测量我冲向讲台时加速度的大小,再与我的质量相乘,都能求出作用在我身上的力的大小

耶鲁公开课 - 基础物理课程节选