Several officials who came to Xinxueguan to be teaching assistants were originally a headache because most of the students in Xinxueguan had no good reputation.

In the past, I was just a little confused in the Academy and I was worried that it would be more difficult to manage after leaving Chang'an when I came to the new Academy.

But what surprised them was that on this first day, everyone's behavior seemed to have changed.

Today, Lao Cui and Lao Du and several teachers began to conduct physical fitness tests on these Wushu members, and they needed to test each of them's physical fitness limits and in which aspect they had more expertise.

In science, Tang Ping personally attended the class.

"I call it a physics class for a class we have today!"

"The so-called physics, you can understand it as the principle of the operation of all things in the world!"

At the front of the classroom, the craftsmen who built the new school museum had long pressed a large wooden board at the front according to Tang Ping's request, and then painted it with black paint.

Tang Ping wrote down two big words "physics" on the blackboard with chalk.

Now these students also know that they cannot whisper at random in class, so even though they have endless questions in their hearts, they can only hold them in their hearts.

Then Tang Ping wrote sixteen big words on the blackboard: "The mystery of the universe, the subtleness of particles, the movement of all things, and the complexity of daily use."

Then he circled the two points behind: "For you now, we can start from the two points behind!"

After saying that, he took out the things he had prepared long ago, which were a small bracket and a wooden board.

First place the middle of the wooden board on the bracket, and after the wooden board is balanced, put a copper coin on it. Then, it is obvious that the end of the wooden board with the copper coin began to sink.

"Who knows what the principle is?" Tang Ping looked at the students below and asked.

"Isn't it because I put the copper coins and gain weight?" Li Tai, who was sitting in the first row, said with some disdain.

I originally thought that this science subject would talk about something, but just now, the sixteen big words written by Tang Ping were also very mysterious, but in the end I really started talking about it, it was that simple thing.

Not to mention now, he almost understood this when he was five years old.

"Okay, then what about I put a copper coin on the other end?" Tang Ping looked at Li Tai and asked.

"Nature will the boards become balanced again!"

"Oh, is that?" Tang Ping smiled and took out another copper plate, but it was different from the one in front of the board on the edge of the wooden board. This time, although he placed the copper plate on the other end, he was closer to the bracket in the middle.

Therefore, the wooden board did not re-balance as Li Tai said, but was still tilted towards the end where the first copper plate was placed, but the amplitude did not begin to grow.

"You...you have to put the copper plates on both ends!" Li Tai said anxiously.

"Okay!" Tang Ping put the second copper plate on the side as he said, and then this time the wooden plate finally returned to balance again.

"So, what is the principle of this?"

Li Tai: “…”

Yes, why? If the same heavy copper plate is placed at different positions of the wooden board, the wooden board will have different inclination angles?

Before he could figure it out, Tang Ping took out another copper plate and asked, "Then if I put two copper plates on one side and only one on the other, what would happen to the wooden plates at this time?"

Li Tai replied without thinking: "Of course, he leaned toward the side where two were placed!"

"Oh, is that?" Or the same words, the same smile.

Then Tang Ping adjusted the position of the wooden board on the bracket and placed the three copper boards on both sides.

This time, the wooden board did not tilt to the side where the two copper boards were placed as Li Tai said, but remained level.

Although Li Tai saw that the wooden board was the same as before, not in the middle of the board, he could not understand the principle.

This is a very simple principle of leverage. The ancients actually used the principle of leverage, but they did not have a complete set of theories to explain this phenomenon.

During the Warring States Period, although the concept of applying leverage was mentioned in Mozi's book "Mozi", there is no detailed explanation for why such a phenomenon occurred.

It took Tang Ping only a few minutes to make this extremely proud Li Tai begin to doubt his life.

But this was not over yet. He took out two more iron balls. The size difference between the two iron balls was very obvious, and then he asked his classic questions again.

"Who will land first when two iron balls, one big and one small, fall from a high place at the same time?"

"I know, land at the same time!" Du He, who was sitting in the middle, shouted loudly, and after shouting, he looked proudly at the classmates around him.

"Still land at the same time?" Li Tai was puzzled, and then muttered in a low voice: "Shouldn't the big one land first?"

Although the sound was very small, he was sitting in the first row and was still heard by Tang Ping.

This time, Tang Ping did not do the experiment first, but drew it on the blackboard.

There is a small circle on the left, a large circle on the right, and a small circle in the middle connects a large circle.

"Li Tai, look, this is a small iron ball, this is a big iron ball, this is a small iron ball and the big iron ball are connected together. Who do you think landing first?"

Li Tai was about to say that the ones connected together, because the ones connected together were obviously the heaviest.

But I stopped before I could even say it, because if the small one fell more slowly, then the small ball and the big ball were connected together, shouldn't it be possible to pull the big ball and delay the speed of the big ball?

This leads to a paradox!

Is Du He's cowardly saying that is right? Are two small balls really landing at the same time?

Li Tai began to doubt his life for the second time.

But it wasn't over yet. Tang Ping took out another feather from the bottom of the platform and asked, "What if the feather and the iron ball fall at the same time?"

"It's better to land at the same time!" Du He shouted behind him, and then a burst of laughter broke out in the classroom.

Because everyone may still have doubts about other things, but who has never seen the scene where the feather slowly falls from a high place? How quickly does the iron ball fall? When the iron ball falls to the ground, the feathers may still be floating.

Du He also realized at this time, yes, the feathers would float, so he turned red and didn't know what to say.

"You think Du He is wrong, don't you?"

"yes!"

"Of course, how slowly did the feathers float down?"

"That's right, how can the feathers land on the ground at the same time as the iron ball?"

Tang Ping smiled and took out another thing from the audience. This was his teaching aid specially purchased online. It was a long glass tube that was vacuumed, with a feather inside it.

"Look, there is a feather in it, right?"

Although the glass long tube that Tang Ping took out looked very shocking in this era, everyone's attention was attracted by the feather inside.

Tang Ping didn't say much, and straightened the glass tube that was almost two meters long.

Then the students below were surprised to find that the feathers here no longer floated slowly when they fell, but fell at an extremely fast speed.

The speed is almost the same as when they usually see other objects falling.
Chapter completed!