I am going to let this arrow somehow indicate the value of the incident energy.

我将用这个箭头来揭示入射能量的值。

youdao

And I have purposely made the arrow shorter to indicate that it has been slowed because we are going to argue its mass didn't change, so the only way to change its energy is to change its velocity.

我已经故意将这个箭头弄短，用来象征它变慢了，因为我们将证明它的质量没有变，只有它的能量改变了，也就是它的速度变了。

youdao

So, we walked to the swimming pool, so not only exercise the body, but also save energy. Is this not shoot two hawks with one arrow?

所以，我们就步行来到了游泳池，这样不仅锻炼了身体，还节约了能源。这难道不是一举两得吗？

youdao

And I am going to let this arrow somehow indicate the value of the incident energy.

我将用这个箭头,来揭示,入射能量的值。

麻省理工公开课 - 固态化学导论课程节选

This incessant march of energy density (more energy per unit of raw material) has undeniable logic extending along the entire length of the arrow of progress.

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