That is, you minimize potential energy and you see things falling under the force of gravity and so forthgoing to potential energy minima in conformance with this result.

换句话说，你使得势能最小化,然后发现我们关注的东西,在重力或者其他力的作用下下落,直到势能最小的地方,这和我们刚才的结果是一致的。

麻省理工公开课 - 热力学与动力学课程节选

You just kind of swept them under the rug, but now, you are out there in full force with your knives sharpened.

只是把它们隐藏起来了，但是现在，竭尽全力站在那儿,拿着削尖了刀。

麻省理工公开课 - 固态化学导论课程节选

If every time I get the same acceleration, I'm convinced this is a reliable spring that is somehow producing the same force under the same condition.

如果每次都能得到相同的加速度,这个弹簧的可靠性就能令人信服,即它在相同的条件下能够产生相等的力

耶鲁公开课 - 基础物理课程节选

Therefore, what we have done now is, we can take all kinds of springs and we can calibrate the force they will exert under various conditions.

因此,我们现在能做到的就是,我们能处理各种各样的弹簧,我们能测出它们在不同的情况下,产生的力的大小

耶鲁公开课 - 基础物理课程节选

I am going to say if that electron is to stay in its orbit, that is to say it doesn't flee the atom, it doesn't collapse under the nucleus then the sum of the forces on the electron must be zero No net force. And so that will be the sum of a dynamic force plus an electrostatic.

如果电子会保持在它的轨道上运行,既不脱离原子的话，它就不会由于原子核对它的吸引力而被瓦解掉,电子所受的合力一定为零,由于没有合力,所以电子所受力为动态力和静电力的总和。

麻省理工公开课 - 固态化学导论课程节选

When you say the rope is under tension being pulled from both sides by a certain force, the tension is not 0 just because this T and that T cancel.

当绳子被绷紧,即两端被拉伸时,拉力并不为 0,因为这个 T 和那个 T 相互抵消了

耶鲁公开课 - 基础物理课程节选