Ang Lee knew that everyone didn't believe that sunlight was colored, after all, whether it was looking at the sun or through objects illuminated by the sun, they could intuitively see that sunlight was not colorful, but Ang Lee said that sunlight was colorful, so they naturally didn't understand it very much.

Of course, what Ang Lee said is the truth, sunlight doesn't look like color, but this is due to the mixing of various colors of light, and what is finally presented is the light we see, as for what color this composite light is, it's really hard to say, it's the most appropriate natural light.

"Haha! I said that light is colored, you don't believe it, because the light you see is not colored, you know why, it's because all kinds of colored light are mixed together, and naturally you can't see color, I know that people won't believe it easily, so let's do two experiments, and after these two experiments are done, you can understand a little bit. ”

After Li An finished speaking, he motioned to the two assistants to immediately start preparing the experimental equipment to complete this very important experiment.

The first experiment is very simple, it is to prepare three spotlights of different colors, connect to the power interface in the lobby to start the experiment, and also need to prepare a white cardboard.

"What kind of fame?"

"Let's just take a look, this is the task given to us by His Majesty, we can complete it seriously, why do we care what Li Shilang does?"

"I'm worried that the emperors and grandchildren will be attracted by these tricks and tricks, and they won't like to learn in the future, so it will be difficult to do."

"That's right! These are all strange skills, ordinary craftsmen just learn it, the emperor is a nobleman, or should learn poetry and etiquette. ”

"The current Datang is in great need of these tricks! This is His Majesty's intention to let the emperor and grandson learn these, but I also think that it is enough to let the excellent craftsmen of the Tang Dynasty understand this, the emperor and grandson are the royal family of the Tang Dynasty, so they will not go to build the machine himself after learning this! ”

"Yes! Where these things should be learned by the emperors and grandchildren, the emperors and grandchildren should learn poetry and book etiquette. ”

"This Li Shilang will do this, I heard that his cooking skills are still very good? The food made is more delicious than that made by the imperial chef in the palace, which is really ...... Ay! ”

Taking advantage of the gap between Li Ang and his assistant to prepare experimental tools, the eight old guys talked in a low voice, anyway, their location is at the end of the lobby, and the distance from Li Ang is the farthest, as long as they are quieter, Li Ang really can't hear it.

And from their words, it can also be clearly seen that in their hearts, only poetry and etiquette are the right way, and the rest are strange and ingenious, not worth mentioning, especially cooking, which is a shameful technique, which is generally only learned by women.

According to later generations, the thinking of these old guys, that is, very typical machismo, how can cooking be a woman's patent? Of course, in the era of the Tang Dynasty, in ordinary families, cooking is indeed a woman's patent, but in many restaurants and restaurants, the situation is a different story, most of the cooks are men, that is, the so-called cooks, and their status is relatively low among all professions, and Li An has a noble status, and he often cooks in person, which makes them very incomprehensible.

The equipment for the experiment was quickly prepared, and Ang Lee first turned on a green spotlight and let it shine light on the white cardboard, and then asked, "Look, what color of light is this?" ”

"Green light is green."

All the emperors and grandsons know that the light is green, and this is too simple.

Then, Ang Lee projected the blue light onto the white cardboard and continued to ask, "Then look at it again, what color is this?" ”

"Blue, it's blue."

The emperors and grandsons were very obedient and answered seriously.

Ang Lee finally turned on another spotlight, and then continued to ask, "What color is this?" ”

"Red, it's red light."

The emperors and grandsons continued to answer.

Ang Lee said with great satisfaction: "Everyone is right, these three beams of light are green light, blue light, and red light, these three beams of light are very clearly displayed on the white cardboard, they are three large spots, red, green, and blue, but do you know what happens after these three beams of light overlap together?" ”

After speaking, he looked at the emperors and grandchildren, and saw their anticipation, so he gently adjusted the angle of the spotlight, so that the three beams of light gradually approached a point, while maintaining a zigzag state of one up and two down.

When the three beams of light partially coincided, the magical phenomenon occurred, the color of the spot where the overlap occurred, the position of the red spot and the green spot coincided became a yellow spot, the position of the green spot and the blue spot became cyan, and the position of the red spot and the blue spot coincided, became magenta, and finally, when the three beams of light all coincided together, all the colors disappeared, and the white cardboard was presented on a big bright spot, in fact, it was a white light, but the cardboard was also white, so, I can't see the color.

After the three beams of light completely coincided, Ang Lee moved them away a little more to show all the overlapping colors just now.

"It's amazing, it's really interesting that different colors of light can change so much when they come together."

"Yes! These children usually fall asleep when they listen to it, but now they are all alive, one is more excited than the other, and they are very serious about listening to the class! ”

"That's not a good thing! In the future, all emperors and grandchildren will love to listen to these strange and obscene lessons, and they will be even more reluctant to learn poetry and etiquette. ”

"This is not false, but this is His Majesty's will, and we can't disobey it!"

"Forget it, let's take one step at a time! If the emperors and grandchildren are not willing to learn poetry and etiquette, we will put the responsibility on Li Shilang, as long as we teach carefully and have a clear conscience. ”

A few old guys muttered to each other.

And these young emperors and grandsons stood up excitedly, and even muttered in confusion.

Li An looked at the emperors and grandchildren, and said loudly: "You have all seen it!" When different colors of light are mixed together, it becomes white, and the same is true for sunlight, which is also colored, but because these various colors of light are all mixed together, it is impossible to see the color, but I have a way to separate the colors of the sun's rays, which is also the next experiment we have to do, and the rainbow is a principle. ”

After saying that, let the two assistants start to prepare for the experiment.

This experiment is very different from the previous experiment, the previous experiment was to combine multiple colors of light, and this experiment is to separate the different colors in the sunlight, so that people can see it very intuitively.

In this experiment, Ang Lee prepared a larger Mitsubishi mirror, which seems to have been done before, but it is estimated that these emperors and grandsons have not seen it, and even if they do, they can do it again to deepen their impression.

To do the prism experiment, you must have direct sunlight, otherwise you can't see anything, but there is no direct sunlight in the house, and the classroom is indoors, so you have to use the emitting mirror.

An assistant walked to the outside of the room with a flat mirror with a tripod, and then, using the reflection principle of the mirror, the sunlight was shot into the room through the window of the room, and pointed it at the position where Ang Lee needed to do the experiment, and then fixed the reflected mirror.

Li An saw that the sunlight had been reflected on his body, so he immediately picked up the Mitsubishi mirror and put it in the position where the light passed, and suddenly, a magical phenomenon was launched, and on the white cardboard behind Li An, a light like a rainbow appeared, very beautiful, very beautiful.

When all the emperors and grandsons saw such a scene, they all stood up with great interest and muttered quietly, and it could be seen that they wanted to know the reason.

It was also the first time for the eight old fellows to see such an experiment, and when they had only heard of it many years ago, they had never seen it with their own eyes, and this miraculous phenomenon surprised them.

It was so surprising that a seemingly inconspicuous Mitsubishi mirror could artificially create a rainbow, and everyone was amazed.

Li An struck while the iron was hot and said: "Through these two experiments, we can already see that the sunlight is colored, but after it is mixed together, it is what we see, but as long as we use the Mitsubishi mirror, we can show the true color of the sun's rays, do you know why?" ”

After speaking, he looked at the emperors and grandchildren.

"Because it's the refraction of light."

An imperial grandson said.

Li An nodded very happily and said: "That's right, this is because different colors of light have different angles of refraction, so after passing through the Mitsubishi mirror, they will appear in different positions, so we can see the rainbow, this is the artificial rainbow, so don't feel strange when you see the rainbow in the future, this is because the refraction of light occurs." ”

"Sir, rainbows always appear after rain, why do the sun's rays only refract after rain? Is it after the rain that there is such a Mitsubishi mirror in the sky? ”

An imperial grandson asked very suspiciously, obviously using his brain.

Li An smiled and said: "You asked very well, rainbows appear after the rain, usually there is none, this is because after the rain, there are still some water vapor in the sky, that is, small water droplets, when the sunlight passes through these small water droplets, it will be refracted to present the true color of the sun, that is, the rainbow we see, but these small water droplets will soon be dried by the sun, so the rainbow will not last very long, or it will disappear completely in a short time, now I understand!" But don't say that you are born with a Mitsubishi mirror, haha! ”

"Hahaha!"

The emperors and grandchildren who were listening to the class all laughed, this atmosphere is incomparable to other courses, it can be seen that the content of Li An's class is interesting, and the emperors and grandchildren like to listen to it very much.

Subsequently, Ang Lee carefully drew the light path diagram of the Mitsubishi mirror refracting different colors of sunlight, and patiently explained, although some people did not understand very well, but it would always have an effect if you spoke a few more times.

After talking about the refraction of light, Li An gave the emperors and grandchildren a moment of time, let them digest and absorb this part of the knowledge, if there is something they don't understand, they can come over and ask at any time, Li An will naturally explain again seriously, these emperors and grandchildren are not fools, as long as they teach seriously, it is impossible to teach them, as long as they believe in themselves.

"Seniors, am I okay?"

In this gap, Ang Lee walked to the back of the lobby and chatted with the eight old guys.

"Li Shilang said it very well! The painting is very attractive to the emperors and grandchildren. ”

"Yes! Oh, yes! This class is the only one where no one dozes off, I watched it a few times, and indeed no one dozes off, haha! ”

"After listening to Li Shilang's class, I also benefited a lot! I used to see rainbows often, but I didn't know that the rainbow was actually formed like this, as long as there is water vapor in the air, it can produce a rainbow, so I don't know, Li Shilang can make a real rainbow, the rainbow seen with the Mitsubishi mirror is straight, compared with the rainbow after the rain, there is still a big gap. ”

"Yes! Oh, yes! According to the meaning of Li Shilang's lecture just now, as long as there is a large amount of water vapor in the air, a rainbow can be produced, and it is not difficult to sprinkle some water into the sky, I wonder if I can see a rainbow! ”

These old guys are obviously still a little unconvinced, and feel that the content of Ang Lee's lecture lacks sufficient basis, and there are many flaws in their opinion.

However, Li An had already prepared, how could he be stumped by these old guys, or he would not make a move, as long as he made a move, he would convince these guys.

"What's so difficult about this, isn't it just to make a real rainbow, I'll let the entourage prepare, you wait a while."

Li An said very carefully, and turned around to explain to the two assistants, asking them to go and prepare immediately.

After waiting for a while, Li An walked to the podium and said: "Today's time is limited, so I can only talk about it here, about the reflection situation, next time, I will take you outside to see the rainbow, although it is not raining now, but you can artificially create some light rain, so that there are small water droplets in the air, so that you can see the rainbow, go, what are we waiting for, go outside to see the rainbow." ”

After speaking, Ang Li took dozens of imperial grandchildren and left the classroom where they were in class and went to the courtyard outside to watch the rainbow.

Seeing Ang Lee like this, the eight old guys naturally didn't dare to ask more, so they had to follow out and see how Ang Lee artificially created the rainbow.

The space in the courtyard is still very large, after all, this is Baisun Courtyard, and there is naturally no shortage of space, and nearby, there is a higher terrace, and two of Ang Lee's assistants went to the higher terrace and carried enough clear water.