Even in the case of this spring, when you pull it, if you pull it to the right by some force.

甚至是在这样的弹簧问题中,当你拉它的时候,如果你用力向右拉

耶鲁公开课 - 基础物理课程节选

In the case of a spring, this is the law that you will deduce.

在弹簧这个例子里,这就是你推导出来的定律

耶鲁公开课 - 基础物理课程节选