Every five or six days, Ang Lee has to go to the emperor's grandson to give a lesson, the last class was about the refraction of light, and this time, the class is mainly about the reflection of light, the content is simpler than the previous class, of course, it will be more interesting.

In this class, Li An still prepared a lot of experimental equipment, and at the same time, two assistants also had to follow, and there was still a chance for them to help.

However, when Li An walked to the Baisun Courtyard, Li An's Baisun Courtyard was quiet, and there was no sound of children reading at all.

"Li Shilang, Your Majesty has just issued an order, and in the future, the place where the emperors and grandchildren will listen to your lectures will be in the Daming Palace, not in the Baisun Courtyard."

Just when Li An was wondering, a little eunuch hurriedly ran over, he had just gone to the R&D center to find Li An, but unfortunately Li An was not there, so he hurried back.

When Li An heard this, he was slightly surprised, paused, and asked, "The emperors and grandchildren have already gone to the palace?" ”

"Yes, Li Shilang, His Majesty personally sent someone to pick him up, just wait for Li Shilang."

The little eunuch replied respectfully.

Li An nodded, got in the car and rushed to Daming Palace.

With the advancement of technology, high-ranking officials in the Tang Dynasty are not riding horses and sedan chairs at the moment, but traveling by car, and Li An is naturally no exception, in addition, because the number of emperors and grandsons is relatively large, they make larger cars, and it is not a problem for a car to accommodate thirty or fifty people.

I had a good class in Baisun Courtyard last time, why did I move the class to Daming Palace this time? Li An thought for a while, and felt that the emperor himself wanted to listen to the class, but as the king of a country, listening to Li An's lectures and treating himself as Li An's student, this is obviously inappropriate, and he is a little difficult to get by, and secretly listening to Li An's lectures is completely different, which can be understood as supervising the study of the emperors and grandchildren, and seeing whether the emperors and grandchildren are serious in class, and the face is completely hanging.

The location of the class is close to the Hanliang Hall of Penglai Pond, where the scenery is better, the field of vision is also relatively broad, and it is not far from the Zichen Hall where the emperor often enters, so it will be very convenient for the emperor to come over.

If you want to see the beautiful scenery around Hanliang Palace, after all, you have to go up to the second floor, but the emperors and grandchildren are here to study, and Li An is also here to give lectures, so they can't just run to the second floor, so they can only stay on the first floor honestly.

However, even through the windows on the first floor, you can see a lot of beautiful scenery, but the scope of the view is a little smaller.

The content of the last class made the emperors and grandchildren very satisfied, so this time, during the class, the emperors and grandchildren seemed very positive, and when they saw Li An from afar, they stood up enthusiastically to say hello, so that Li An was not excited.

When entering the main hall, Li An saw that in addition to dozens of imperial grandsons, there were also two gentlemen sitting in charge, compared to the eight old guys last time, it was three-quarters less, and other than that, there was no one else.

However, there are wings on both sides of the main hall, separated by a thin wooden screen in the middle, and whether there is someone behind the screen, Li An does not know.

After the class, Li Ang first had to prepare the various instruments for the experiment, and let the two assistants complete them.

"Students, the last class was about the refraction of light, this class, we are going to talk about the reflection of light, about the last class, do you all understand?"

Li An said.

The answers of the emperors and grandchildren were strange, some said they understood, some didn't understand, some asked questions, and even asked Ang Lee to talk about it again, and even, some wanted to see the rainbow.

Ang Lee explained a little and briefly revisited the refraction of light, and then went to the main topic and began to explain the content of this lesson, that is, the reflection of light.

Before the lecture, the first thing to do is, of course, to do experiments, only through more intuitive experiments, can children better understand what is going on with the reflection of light.

Ang Lee first prepared a mirror, and then, he also prepared a flashlight, which was a gadget that had just been invented, and then the experiment began.

One assistant holds a flat mirror in both hands, another holds a white panel, and Ang Lee holds a flashlight and shines it on the mirror, and then, gently moving the angle of the flashlight, you can see that the position of the light spot reflected on the whiteboard is constantly changing.

Then, Ang Lee changed the angle, put the flat mirror on the table in front of him, and then continued to do this experiment so that the emperors and grandchildren could see more clearly.

"Have you seen clearly, the light hits the mirror from different angles, and the angle of reflection is different, now draw a picture for you to see."

Li An said and drew a light path diagram on the blackboard, and then explained it in great detail, because the experiment had already been done, so these emperors and grandsons understood the principle of reflection after listening to it for a while, and also knew what the angle of incidence and reflection was, and felt very happy.

"Students, what do you usually encounter about the reflection of light?"

After Ang Lee finished reasoning, he was going to ask them next.

"The room facing north is darker, and if you look at the reflective wall outside, the room facing north will become much brighter, which is the reflection of light."

"The moon in the water can be seen at night, which is caused by the reflection of moonlight on the surface of the water."

The emperors and grandsons gave a lot of examples in one breath, and they were all right.

Li An was very happy, praised all the emperors and grandsons who answered the questions, and then took out the treasures he had prepared, two periscopes that had just been made some time ago.

"Students, this is a periscope, and it is retractable, the periscope also uses the principle of light reflection, I will draw the optical path diagram later, everyone try the periscope first, Li Shi, you come first."

Li An pulled Li Shi up as he spoke, and taught him how to use it.

A simple toy like a periscope was naturally difficult for Li Shi, and he quickly learned how to use this tool and played with it very happily.

Playing in the room does not reflect the huge role of the periscope, if you want to play with the periscope better, you still have to go out to play, so Li An took a group of imperial grandsons to the outside of the Hanliang Palace.

In front of Li An is a brick wall that is taller than any adult, because of the obstruction of the high wall, so you can't see what the situation is on the other side of the high wall, and with this periscope, you don't have to worry, as long as you take out the periscope, you can easily see the situation on the other side of the high wall.

Li An personally held a periscope, tried to adjust the length, and saw the scenery behind the high wall, because the Hanliang Hall is close to Penglai Pool, so the scenery behind the high wall is very beautiful, there are mountains and water, as well as blooming flowers, and even, you can see a beautiful artificial rainbow.

Because the number of emperors and grandchildren is relatively large, but there are only two periscopes, the emperors and grandchildren can only use the periscopes in turn, and each person can only use them for a moment, and then they must be handed over to the next person.

All the emperors and grandchildren lined up and went to experience the fun of periscopes one by one, many of them had not yet enjoyed themselves, and the periscopes in their hands had been snatched by the people behind.

Of course, in order to better see the distant scene, the periscope applies the refraction of light in addition to the reflection of light, otherwise, due to the distance of light propagation, the scene seen from the periscope will be smaller than what is seen directly with the eye, and in order to better appreciate the scene, the internal light path map can be adjusted, so that the scene seen by the eye is larger and clearer, of course, due to the limitation of the field of vision, the larger the scene seen, the smaller the range that can be seen, and the range that you want to see becomes larger, Then the object you see will be smaller, which is the same principle as a magnifying glass.

Because of time, Ang Lee did not develop a periscope that could adjust the scope of the scene, but only invented a fixed periscope. The most ordinary kind.

Dozens of imperial grandchildren, one by one, all tried it out, and praised the periscope invented by Ang Lee, thinking that the periscope was a very fun and interesting toy, and even, in order to see more at the other end of the high wall, they snatched the periscope from each other, and the scene was a little chaotic for a while, which scared the two old guys and hurriedly came forward to maintain order.

Actually, all the emperors and grandsons have already seen the periscope, so Li An will lead them back to the house, and draw the light path of the periscope, and then explain it to let them understand the principle of the periscope, which is to use the refraction of light.

"Periscope? It's interesting, you go get one, I'm going to see it. ”

Li Longji was in a nearby room, he had already seen Ang Lee's performance, and thought it was very interesting, so when everyone returned to the house, he asked the little eunuch to ask for a periscope, he really wanted to see for himself, whether this periscope was really so magical.

"Li Shilang, wait a minute, Your Majesty wants to see the periscope."

A little eunuch walked over and looked at the periscope in Ang Lee's hand.

Li An looked at the imperial grandson who had all entered the house, looked back at the surroundings, and asked in a low voice, "Your Majesty is nearby?" ”

"That's right, Your Majesty has been here for a long time, and you still praise Li Shilang for speaking well?"

The little eunuch didn't hide it, and spoke.

Li An smiled, handed the periscope in his hand to the little eunuch, and then walked into the room and continued to lecture.

After Li Longji got the periscope, he tried to look at it and found that it was really a good thing, so he didn't understand, why was Li Ang so smart? Anything strange can be invented.

"I've got this thing."

Li Longji was very domineering and took possession of the periscope that Li An had worked so hard to make, and left with the telescope after speaking.

Li An continued to take the class, drawing the model of the periscope and the internal optical path diagram, and continued to explain all kinds until all the emperors and grandsons could understand it.

"Okay, the content of this lesson has been finished, and the class is over."

After Li An finished speaking, he asked the two assistants behind him to start packing, put all the things he brought into the back basket, and then brought them back, leaving only a periscope and giving it to the eldest son of the emperor's eldest grandson, that is, the emperor's grandson Li Shi, who gave him the highest status?

Li Shi is very lively, after getting the periscope, he jumped out with a swish, and ran to the outside of the high wall, the long periscope in the depths, to see the scenery on the other side of the high wall, and behind Li Shi, followed by a large group of emperors and grandchildren, they were all waiting and asking, waiting for Li Shi to see enough, giving them the periscope to play with, and there were many emperors and grandchildren, and kept asking what they saw.

"Li Huai, why don't you go to play?"

Seeing that all the emperors and grandsons ran out to play with periscopes, and even the two old guys went out to watch the excitement, but Li Huai stayed in the house and didn't leave, Li An asked curiously.

Li Huai walked up to Li An and said sincerely: "My father said that I want to thank you and let me learn science with you." ”

"Oh, how is your father now, is he okay?"

Ang Lee asked.

Li Huai's eyes showed a look of joy, and he said: "Father is very good, much better than before, he will smile, and he hugged me this morning." ”

"Oh, so your father is holding you for the first time this morning?"

Ang Lee asked with a smile.

"Yes, my father never hugged me before, but now he has become better, thanks to Mr., I will study hard."

Li Huai smiled innocently, seemed very satisfied, paused, and then said: "Father said that he is very close to Mr., and he will visit him when he has time to ask Mr. for advice." ”

"Oh, King Shou is going to come to the door to ask for advice, okay, go back and tell your father, as long as he is free, he can go to my house at any time."

Li Ang said very hospitablely.

Although I don't know what Li Mao is going to do, as a very hospitable person, Ang Lee will not refuse Li Mao's request, not only for Li Mao, but also for anyone who wants to visit him, Ang Lee will not turn him away.

As for Li Mao's identity is too special, many people avoid it, but Li An doesn't think so, even if the emperor robbed Li Mao's princess, but their relationship is father and son after all, and, after so many years, the emperor has no intention of killing him, obviously, the emperor still loves this son very much in his heart, but looking at the world, there is really no woman who can surpass the feeling that Yang Yuhuan gave him, and the emperor needs this feeling very much, so he risked the world's disapproval and robbed his son's princess, But in the emperor's heart, there was still some guilt to a greater or lesser extent.

The worse King Shou is, the more serious the guilt in the emperor's heart, and if King Shou can live better and healthier, the emperor's heart will feel better, in order to take care of this son, he deliberately chose a princess personally, and after being a famous family in the capital, he did not insult Li Mao.

And seeing that Li Mao and Wei's gave birth to many children in a row, Li Longji's heart is still relatively happy, as long as his son completely forgets about Yang Yuhuan and lives happily, he is very satisfied.