One way to mark time is to imagine it carries a clock as it moves, and put markers every second.

标记时间的一种方法是,想像它带着时钟运动,并且每秒做一次标记

耶鲁公开课 - 基础物理课程节选

The way the physics works is you will find some laws of motion in mathematical form, you put in the initial conditions of whatever, you solve the equations, and the answer that comes, you have no choice.

在物理问题中,你可以用数学方法得到运动定律,你代入初始条件,然后解方程,获得答案,你别无选择

耶鲁公开课 - 基础物理课程节选