Now to start with, the plasmid is usually shown in a diagram like this as a circle.

首先要说的是,质粒通常用图中这个环形来表示

耶鲁公开课 - 生物医学工程探索课程节选

Suppose the particle is not moving in a circle, but does this.

假设这个质点不是做圆周运动,而是这样

耶鲁公开课 - 基础物理课程节选

So in hydrogen atom a, I'll depict that here where the nucleus is this dot, and then the circle is what I'm depicting as the wave function.

在氢原子A里，我在这里把原子核画成一个点，这圆就是波函数。

麻省理工公开课 - 化学原理课程节选

This describes a particle that's going around in a circle.

这个式子描述了质点的圆周运动

耶鲁公开课 - 基础物理课程节选

When a particle moves in a circle, it has an acceleration towards the center of this size, v^2 over R.

当一个质点在圆周上运动时,它有一个指向圆心的加速度,v^2 / R

耶鲁公开课 - 基础物理课程节选

We know it's going around in a circle because if I find the length of this vector, which is the x-square part, plus the y-square part, I just get r square at all times, because sine square plus cosine square is one.

我们之所以知道它做圆周运动,是因为我求出了这个矢量的模长,也就是 x 的平方加上 y 的平方,我就得到了它在任意时刻的模长平方,因为正弦平方加余弦平方始终等于1

耶鲁公开课 - 基础物理课程节选