Xueba, I beg you to go and escort him quickly!

Zhu Tiesen became more and more curious, what kind of group is that group?

Xu Heng, "Want to have lunch together?"

The group leader and the others shook their heads, "We arranged it together, and we ran out sneakily!"

"By the way, Mr. Xu Heng, when are you going to the classroom?"

"There are only 99 people in the class now, and I knew you were one!"

"Ring Ling Ling..."

Several people were chattering, and suddenly the phone rang.

The group leader was startled, "Hurry up, hurry up! The teacher called to remind you!"

"Xu Heng, let's go! Bye, senior! Bye, teacher!"

Several people come and go like the wind!

Xu Heng smiled helplessly.

Zhou Moyan and Fu Xidong ordered food and sat down.

While eating, Zhou Moyan raced against the clock, swiping his phone.

Of course it's not for playing, but for brushing questions.

He looked at Xu Heng and asked, "Together?"

Xu Heng smiled, "Look at yours! I'm not interested."

Zhu Tiesen didn't know about Xu Heng's talent in the field of physics.

So he was a little confused.

"Zhou Moyan, you should be studying physics, right?"

Zhou Moyan froze for a moment, "Yes, teacher, what do you mean?"

"You are junior, I remember!"

Zhou Moyan continued to nod.

So?

"hiss……!"

Zhu Tiesen took a breath and turned to look at Xu Heng.

"So, Zhou Moyan's question should be a junior or postgraduate entrance examination question? Xu Heng, can you get in on this?"

Fu Xidong on the side smiled, "Teacher, you don't know Xu Heng, right? He should be best at physics! The postgraduate entrance examination questions are a piece of cake for him!"

"You don't know?"

For him, the postgraduate entrance examination questions... are all a piece of cake? !

Zhu Tiesen's scalp was numb, but he really didn't know.

"hiss……!!!"

Jutsen looked at Xu Heng with shock in his eyes.

Zhou Moyan, "It's just right, I also have a question, I want to ask you for advice! Xu Heng, take a look."

topic:

A very long rectangular U-shaped guide rail forms an angle θ with the horizontal plane. The Luo wire can slide on the guide rail without friction. The guide rail is located in the uniform magnetic field with the magnetic induction intensity B vertically upward.

Let the mass of wire ab be m, the resistance be R, the length be l, the resistance of the guide rail be ignored, and abcd form a circuit.

When t=0, v=0.

Zhou Moyan, "Find the functional relationship between the speed v of the wire ab sliding down and the time t!"

"Also, request the maximum speed vm of wire ab!"

Xu Heng looked at the question while eating, and said after a while, "This test is about the kinetic electromotive force caused by the movement of the object and cutting the magnetic induction line!"

"Such a simple question, you come to ask me, you are from the Yao class!"

"At the beginning, I really didn't know Yao Ban, but after I checked it, I understood it! That is the Tsinghua of Tsinghua!"

"Senior Zhou, did you do it on purpose?"

"Are you asking me to answer the question on purpose, to prove it to Professor Zhu?"

Xu Heng waved his hand, "It's not necessary! Professor Zhu knows me quite well!"

Professor Zhu turned his back on the spot, "No, no, no! Tell me!"

Xu Heng's whole body is not good.

"%%#￥###￥..."

"Hey, hey! Professor Zhu, what about the trust between people?"

"Besides, you teach mathematics! You have a specialization in mathematics! Don't make trouble!"

Professor Zhu refused, "Although I don't understand it, there are people who understand it!"

He looked at Zhou Moyan and Fu Xidong.

Fu Xidong first clarified, "I'm a freshman, and I don't understand this postgraduate entrance examination question! Senior Zhou should check it out!"

"Student Xu Heng, please!"

Looking at Zhu Tiesen, Fu Xidong, Zhou Moyan, and Xu Heng who looked expectant, "%￥##￥￥..."

They are on purpose!

I just want to see Xu Heng's strength in person!

They wanted to see it for themselves.

Xu Heng looked at the question reluctantly.

Fu Xidong, "Do you need a pen and paper?"

Xu Heng ate while watching.

Four or five minutes later, after Xu Heng finished eating, he slowly opened his mouth, "The kinetic electromotive force of the wire ab is... the direction is from b to a, and the direction of the ampere force is to the right..."

"Gravity is projected on the guide rail down the guide rail with a magnitude of mgsinθ."

"mgsinθ=(vB2l2cos2θ)/R=ma=mdv/dt."

“就可以得到v=[（mgRsinθ）/（B2l2cos2θ）][1-e（-（B2l2cos2θ）t/（mR）次方）]。”

"The maximum pressing speed of wire ab in the second question, vm=(mgRsinθ)/(B2l2cos2θ)."

Xu Heng finished speaking expressionlessly.

Both Zhu Tiesen and Fu Xidong stared at Zhou Moyan.

After Zhou Moyan nodded slowly, the two of them felt their scalps go numb.

I know Xu Heng is amazing!

The postgraduate entrance examination questions are a piece of cake for him!

But from reading the questions to Xu Heng giving the answer, it only took a few minutes!

The point is, he still does calculations in his head, he doesn't even need a pen and paper!

Fu Xidong, "!!!"

Zhu Tiesen, "!!!"

Zhou Moyan, "!!!"

Even though the three people present were mentally prepared, they were still shocked.

Face to face, the impact of being given the answer directly!

It can't be reflected through the mobile phone or along the Internet!

It's so exciting!

It's like riding a longer and higher roller coaster!

Whoosh whoosh!

The impact is too strong!

For a while, Zhu Tiesen still hadn't recovered.

Although he is a professor in the Department of Mathematics, he is not a fool. He can distinguish the difficulty of this question just by listening to Xu Heng's answer.

Xu Heng, "So, is it okay? Three?"

Fu Xidong came back to his senses with a smile on his face. He looked at Xu Heng with admiration far better than Zhou Moyan.

Zhu Tiesen knew this look, it was exactly the same as the eyes of the students who just participated in the Olympiad competition.

It's like looking at an idol!

"You continue to eat, I will wait for you."

In order to wait for Xu Heng to give the answer, the three of them forgot to eat!

It was only at this time that I came back to my senses, and started to gobble up one by one.

That's all for Zhou Moyan and Fu Xidong. I didn't expect Zhu Tiesen to do the same.

In the afternoon, Xu Heng, Zhou Moyan and Fu Xidong experienced the Tsinghua campus together.

"This is the library, do you want to go in and have a look?"

"This place has won the National Excellent Engineering Gold Award!"

· · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · ·??????????????

"Some people say: architecture is frozen music. If you regard the architecture of Tsinghua Garden as a piece of music with beautiful tunes and high melody, the library is undoubtedly one of the most beautiful notes in this piece of music."

"No matter spring or summer or autumn or winter, no matter whether the sun is rising or the red wheel is setting in the west, whenever you walk into the library of Tsinghua University, you will be greeted with a faint fragrance of books, and what you will see are the hardworking figures of the students."

"Here is the ocean of knowledge, here is the world of seeking knowledge, here is the spiritual home leading to the other shore, here is the road to success leading to glory..."

Zhou Moyan's words are perfect.

Xu Heng smiled and followed them to the library.

Zhou Moyan, "I'm going to look for some physics books in the library."

The same goes for Fu Xidong, he is also from the Department of Physics, and in terms of reading, he still counts on Zhou Moyan to help him find some books.

Xu Heng stopped and walked.

I found one that I was interested in, but after flipping through it, I found that it was not that profound, so I put it down.

After searching, Xu Heng found that Zhou Moyan had already sat down and was reading a book.

He looked very seriously.

Occasionally raised his head and looked at Xu Heng.

The first time, Xu Heng was standing; the second time, Xu Heng was still standing; the third time...

Zhou Moyan, "???"

Why is he still standing!

Zhou Moyan got up and asked Xu Heng to sit in his seat, while he went to the bookshelf to look for books.

Xu Heng just sat down, and within a few minutes, a female classmate next to him came over.

She didn't raise her head, she just whispered, "Senior...can you help me with this question?"

+0 0 0 [-]

Xu Heng, "???"

He looked at this female classmate, even if it was a question, she didn't look up, so Xu Heng can be sure that she regards herself as Zhou Moyan.

At the same time as the purpose of the question, the female classmate continued to calculate her own.

Xu Heng, pick up the pen and paper from Zhou Moyan.