The Texas researchers estimated the energy intensity of preparing food from agriculture, transportation,processing and food sales.

VOA: special.2010.11.23

So, what we would expect is that there is a relationship between intensity in kinetic energy because it was understood that however intense the light was, if you had a more intense light, it was a higher energy light beam.

光强和能量之间,应该有一定的关系,因为在我们的理解中,不管光强是多少，光的强度越大,光束能量越高。

麻省理工公开课 - 化学原理课程节选

The next thing that they wanted to look at was the actual intensity of the light and see what the relationship of intensity to kinetic energy is.

下一而他们要研究的是光的强度,看一下光强和能量之间的,关系是怎样的，我们预期。

麻省理工公开课 - 化学原理课程节选

Intensity, if we increase the intensity, we're not increasing the energy in each photon, we're just increasing the number of photons that we're shooting out of our laser, whatever our light source is.

强度，如果我们增加强度，我们增加的不是,每个光子的能量，我们增加的仅仅是,从我们激光源射出的光子数，无论我们的光源是什么。

麻省理工公开课 - 化学原理课程节选

So we see that we do not eject electrons in the case of the laser pointer, even if we have this intensity, it is still not related to the energy of an individual photon, so we won't see an effect.

所以我们看到我们用激光笔,还是没有逐出电子，即使我们有这样的强度，它仍然与一个单个的光子能量无关,所以我们不会看到光电效应。

麻省理工公开课 - 化学原理课程节选

And this is what they had expected that there would be no relationship, but instead here they saw that there was a linear relationship not to the intensity and the kinetic energy of the electrons, but to the intensity and the number of electrons.

另外一个实验,他们预期这两者没有关系,但他们看到的不是,光强和电子动能的,线性关系，而是光强,和电子数的线性关系。

麻省理工公开课 - 化学原理课程节选

So that should mean that the energy that's transferred to the electron should be greater, but that's not what you saw at all, and what you saw is that if you kept the frequency constant there was absolutely no change in the kinetic energy of the electrons, no matter how high up you had the intensity of the light go.

所以这意味着转移到电子,上的能量也越大，但这并不是，我们观测到的现象,我们所看到的是,如果固定光的频率不变,不管光强如何变化,电子的动能没有任何变化。

麻省理工公开课 - 化学原理课程节选

Also, what's the energy per photon of this red laser pointer, and then it's also worth trying a calculation dealing with intensity. So let's also try calculating the numbers of photons that would be emitted by this laser pointer, if, for example, we were to use it for 60 seconds and this were a one milliwatt laser.

同样，红色激光笔的,每个光子能量是多少，这也值得用处理强度的方法计算一下,让我们也计算一下,有多少光子会从这个激光笔射出，举个例子，如果我们使用它持续60秒,这里会有一毫瓦的激光。

麻省理工公开课 - 化学原理课程节选