If a photon which has no mass can behave as a particle, does it follow then an electron which has mass can behave as a wave? 1920.

如果一个没有质量的光子,能像粒子一样运动，那么它能像一个,没有质量的电子那样以波的形式运动吗。

麻省理工公开课 - 固态化学导论课程节选

If a photon, which has no mass, can behave as a particle --And we know this.

如果一个没有质量的光子，像粒子一样运动--，我们知道这个。

麻省理工公开课 - 固态化学导论课程节选

And know intuitively that if they move together, they will behave like an object of mass 5 and the acceleration will again be 2.

凭直觉认为既然它们一起运动,那么它们就相当于一个质量为 5 千克的物体,然后我们可以算出加速度为 2

耶鲁公开课 - 基础物理课程节选

That is why we don't worry about the motion of the nucleus 1 because the ratio of mass is about 2,000 to one.

这就解释了为什么我们不担心,原子核运动起来,因为原子核和电子的质量比约为2000：

麻省理工公开课 - 固态化学导论课程节选

This spring is getting squashed on either side, and it'll squash by certain amount x, that depends on your mass, and that x will be turned into a motion of a needle and that'll read your mass.

这个弹簧两边都会受到压缩,压缩量为 x,它由你的质量决定,x 会转换成指针的运动,你从而可以读数

耶鲁公开课 - 基础物理课程节选