Daming: Grandpa Emperor, please get up and sit on my throne!

Xu Miaojin looked at the paper and nodded without saying anything.

Zhu Yunhuan continued, "When it was here, the light was moving in the void. When the light reached the position of this piece of specially shaped colored glass, there was colored glass in front of it. The void and the colored glass are made of different materials..."

Next, Zhu Yunhuan explained the basic concepts such as air, glass, medium, refractive index, etc. in a simple and easy-to-understand way.

Then the focal length and imaging rules of convex lenses were gradually introduced.

Including prisms, different colors of light finally projecting a rainbow phenomenon on the table, etc.

Originally, what Xu Miaojin was most interested in was the content of this issue of the newspaper.

But as Zhu Yunhuan took out the convex lens and prism and talked about things that she had never heard of or thought about before, Xu Miaojin's mind gradually sank into it. Although the voice of the storyteller outside and the voices of customers talking and cheering still came in, it seemed that they could no longer reach her ears.

One person is talking and the other is listening, like a teacher and a student.

Xu Miaojin was ignorant from the beginning, like a dry sponge put into water, madly absorbing the moisture of knowledge, and step by step opened the door to a new world...

"So... in fact, if we master this principle, as long as the thickness of this magnifying glass is moderate, the magnification can even be more than the current 20 to 30 times, or even higher!" Xu Miaojin said, holding the convex lens in his hand, looking at it thoughtfully.

Zhu Yunhuan nodded and said, "This child is teachable."

Xu Miaojin did show different talents, with strong comprehension and understanding abilities, and was more receptive to new things than those mathematics doctors in the Imperial College.

This is also the reason why Zhu Yunhuan was willing to talk so much to a little girl - a smart and clever child is willing to think and understand seriously what you teach and say, and many times she will understand it immediately and with great energy.

To put it bluntly, teachers will prefer such students.

But on second thought, it seems to make sense.

Older people usually have rigid ideas. Even if they have the intelligence, their brains lack flexibility and curiosity.

Although Xu Miaojin had extraordinary knowledge and cognition, according to her age, she would only be a junior high school student who had just graduated from primary school in the future. It was the right time for her to start learning physics and chemistry.

Time passed by minute by minute.

Before they knew it, a gavel bang was heard outside: "This is the content of the third issue of the newspaper. If you want to know the content of the next issue of the newspaper, we will continue to analyze it in ten days!" There were also bursts of noisy voices coming from the crowd.

Zhu Yunhuan looked at the time, raised his eyebrows and said, "It's already this late, it seems I don't have time to go to the auction house today." He didn't expect that he had just planned to talk casually, but as he was talking and Xu Miaojin was asking questions, he had already read all the newspapers outside.

"You...are leaving?"

Xu Miaojin frowned slightly, with a hint of anxiety in her eyes.

Xu Miaojin just felt.

It felt like not much time had passed.

Zhu Yunhuan nodded and said nonsense seriously: "There are many businesses at home waiting for me to deal with them."

It's already this point, and he's the emperor with a ton of things on his hands. He comes out just to take a break from his busy schedule, so of course he doesn't have time to hang around outside the palace all day long.

After saying that, he stood up, nodded politely, and slowly walked towards the door.

Although I didn't go to the auction house today.

But for Zhu Yunhuan, it was also a different kind of gain. At least he had a good student, and at least the idea of ​​mathematics and physics that had been in his mind for a long time had a beginning.

Xu Miaojin pursed her lips slightly, wanting to say something but hesitant.

Zhu Yunhuan turned around and asked calmly, "What's the matter?"